Comparing our Gelasimus larva, artificially removed from the egg, with Faxon's beautiful figures1 (1, 2) of the embryonic zoëa of Carcinus shortly before hatching (his Fig. 9 representing the larva in the act of exuviating the larval skin);2 the first antennæ are seen to be much shorter and proportionately stouter than in the remarkably developed antennæ of Carcinus, being more as in the zoëa stage; the second antennæ have nearly the same general form as in the zoëa after molting; the spine (exopodite), squamiform appendage (endopodite), and rudimentary flagellum being indicated. The antennæ of our embryo Gelasimus do not appear, then, to have the great development found by Faxon to exist in Carcinus of the same or nearly the same age. Faxon has not represented the first maxillæ, but it is two-lobed, the lower larger lobe probably being later in life differentiated into two endopodites; the second maxillæ differ from Faxon's figure of the embryonic zoëa of Panopæus in not being divided into four endopodites equal in size and form, but into three endopodites, the second (v en2) being deeply lobed, and the third (v en3) being twojointed. They, however, are nearly identical in form with the second maxillæ of Cyclograpsus as figured by Müller.3 The endopodites of the first and second maxillipeds differ from those of Carcinus in having five joints, Carcinus having four joints to the endopodites of the first pair and only two in the second pair; in Cyclograpsus, however, Müller figures three, and as Gelasimus stands higher in the series than Cyclograpsus, it is possible that Gelasimus is, in this respect, more differentiated. (All of my drawings were made with the camera, though it is possible I may have been in error in drawing too many joints.) The tail of our embryonic Gelasimus also shows no such extreme development as discovered in Carcinus by Faxon, and in this respect it is like Cyclograpsus (Müller's Fig. 18); and hence I am inclined to the supposition that Gelasimus before the first 1On some points in the structure of the embryonic zoëa. By Walter Faxon. Bulletin Mus. Comp. Zoology, vi, No. 10. Pl. 11, Fig. 1. 2 We see no reason for not homologizing this membrane with the amnion of insects and of Limulus and Apus. 3 See Facts for Darwin. English translation, p. 50, Fig. 18. Our Gelasimus zoëa appears to agree much more closely with the zoëa of Müller's marsh crab (Cyclograpsus) than with that of Carcinus or Panopeus, but in Müller's figure the endopodites of the second pair of maxillipeds are drawn as three-jointed. His zoëa has a dorsal and frontal spine, and represents a more advanced stage than our Gelasimus embryo. molt, after hatching, does not exhibit the strange and suggestive antennal and caudal features described by Mr. Faxon, and which he has interpreted so ably.1 An Abbreviated Metamorphosis in Alpheus heterochelis.—This species and Alpheus minus Say, are very abundant, living in the larger excurrent orifices of the large sponges which exist from the depth of one or two feet or more to deeper water, at Key West, Florida. A. minus is, however, far more abundant than the larger species. I found several of A. heterochelis with far advanced embryo, in the winter of 1869-70, and on removing the embryonic zoëa from the egg, was interested to find that the larva was of a form much more advanced than in the zoëa of other Anomoura described and figured by Fritz Müller in his suggestive work entitled "Facts for Darwin." Indeed the metamorphosis appears to be abbreviated, and the larva on hatching closely approximates the form of the adult, as in the case of the development of the lobster, the crawfish, and of Palamon adspersus and Eriphia spinifrons (the three latter observed by Rathke). The eyes were developed on very short peduncles, being almost sessile. The embryo was near the time of hatching, though the yolk was not entirely absorbed. The two pairs of antennæ were well developed and hung down behind the large claws; the five pairs of legs were well developed, the joints distinct, and the first pair were about twice as thick as the others, the claws rather large, but not so disproportionately so as in the adult form, but as much so as in the larva in the second stage of the lobster, figured by Professor Smith. The eyes were large, but nearly sessile. The abdomen was broad and flat, spatulate at the end much as in the adult; there were five pairs of abdominal feet or swimmerets (Fig. 1E), each with an endopodite and exopodite, like those seen in the second larval stage of the lobster. 'It was not until the greater part of this article was written that I saw that Mr. Faxon has raised Gelasimus pugnax from the egg for the express purpose of examining the embryonic cuticle, and that he has figured the forked tail of the first zoča on his second plate, figure 11, which closely resembles that of the first stage of the zoëa of Carcinus. Had I noticed that he had studied the development of Gelasimus, I should not have attempted to write out my notes, but conclude to offer the remarks in this article subject to future corrections. Mr. Faxon does not state whether Gelasimus undergoes the sub-zoëal stage of Carcinus or not, and which our observations indicate do not probably exist. We would, in passing, suggest that the term sub-zoëa be applied to the zoea before the amnion is thrown off, as it corresponds in a degree to the fleshy-hatched larva of the grasshoppers, myriapods and other Tracheata before the amnion is exuviated. It thus appears that Alpheus heterochelis hatches in a stage more advanced than the first larval stage of the lobster. Unfortunately the specimens, though carefully preserved for several years, finally got misplaced, so that it is not possible for us to give a more detailed description of the young at the time of birth. :0: REASON-A PSYCHOLOGICAL DISTINCTION. FROM BY HARLEY BARNES. ROM its peculiar sphere, psychology requires a very close and rigid discrimination in the use of words. A prevalent looseness in this respect is a prolific source of confusion and misunderstanding in the discussion of this and similar questions. An article in the August NATURALIST, entitled "The Reasoning Faculty of Animals," contains a number of interesting facts showing that the lower animals have the power of “reason;" this term is defined as "the power by means of which one proposition is deduced from another, and of forming a conclusion from known premises." This is truly the faculty of reasoning-a part of the understanding-but reason, as understood by psychologists, comprehends far more than this. The classification used in the editorial on insanity in the same number, and now generally accepted, I believe, places all mental operations in three great classes the intellect, the emotions and the will. Continuing this division according to Hickok and others, we have the powers of the intellect arranged in three very distinct groups, called the sense, the understanding and the reason. A few words of explanation will make the arrangement plain. Sense is the name given to that operation of the intellect which forces a constant flow of perceptions upon the field of consciousness. These may be perceptions of the five (or six) senses, internal perceptions of our own feelings and emotions, or the vague creations of a wandering judgmentless fancy common to children, savages, inebriates and opium-eaters. All these perceptions flow in an unconnected, unceasing train across the mirror of consciousness, and are as momentary as the beating of sound-waves against the tympanum. This gives occasion for the second operation of the intellect, called the understanding, by which these separate perceptions are placed in their proper relation to each other, giving ideas of definite, distinct substances, and of their reciprocal action in cause and effect. These operations, including the higher form of abstract reasoning, involve the use of the faculties of memory, reflection, association, abstraction, etc., and the formation of logical judgments. The processes of the understanding, working upon the perceptions of sense, weave all the facts of nature into one endless chain of effects, each dependent upon its foregoing cause. In pursuing such a train of thought there can, of course, be no departure from the real and tangible; no approach to the unconditional to the primal cause. There can be no conception of any power above nature because the understanding considers only natural facts for which it assigns natural causes; hence there can be no rising above the things known to the manner of knowing, nor above limited time and space to the Infinite, nor above conditioned power and truth and beauty and goodness to the Absolute. All these grander conceptions, distinct from judgments of the understanding in their scope, their creation, and the principles which underlie them, are the products of reason, the queen of the intellectual trinity and the vivifier of intellectual activity. The lower animals have the power of sense, their perceptive faculties being often better developed than those of man, though usually not in so great a variety. They also have the power of understanding, to a variable extent; can learn from experience, reason from cause to effect, and by association of ideas; in some cases the memory is capable of considerable development. It is freely granted by all unprejudiced thinkers, I believe, that there is a possibility for the irresponsible animals to reach the very highest attainments of the understanding, though in every instance yet recorded they fall immeasurably below them. beyond this limit they can never go; they are a part of nature and amenable to natural laws, mentally as well as physically; to modify, Hamilton's famous conclusion, "the animal mind can never know the unconditioned." The animal mind can discover but can never invent; it can utilize and explain, but can never originate. It can have none of those thoughts commonly ascribed to morality, no appreciation of the beautiful, no knowledge of truth, no conception of the infinite and the absolute. But EDITORS' TABLE. EDITORS: A. S. PACKARD, JR., AND E. D. COPE. We publish to-day a short critique, by Mr. Harley Barnes, on Mr. James' article on animal reason, which appeared in the August NATURALIST. This gentleman maintains the characters of reason as distinct from the understanding. He defines the former as the power of invention as distinguished from discovery. The understanding "can utilize and explain, but not originate. It can have none of those thoughts commonly ascribed to morality, no appreciation of the beautiful, no knowledge of truth, no conception of the infinite and the absolute." All these qualities are ascribed to reason. We think that if this be the definition of reason, that we can show that the latter has no existence whatever. Thus we deny that man has any conception of "absolute" and “infinite." They are words which do not represent ideas, just as the statement "twice two equals six," relates to nothing either objective or subjective. They belong to Spencer's class of "pseudideas." As to the "knowledge of truth," anything correctly known by animal or man is truth, and animals know a good deal of it. The "appreciation of the beautiful" is well developed in many animals, more, it seems to us, than in some men. "Thoughts commonly ascribed to morality" apparently exist in some animals, especially the dog; while they are feebly developed in some races of savage men. The superiority of men is to be conceded here, but if morality be an attribute of reason, then traces of this reason are discoverable among some lower animals. The powers of origination and invention here ascribed to man and to reason, as distinguished from the "understanding' of the lower animals, even when most orignal, are of doubtful existence. They consist generally of combinations of a few first principles already learned through experience or confirmed by experience. Musical composition is probably derived from rhythmical movements of certain brain elements, which are favored by feeble vitality of the parts, and which are combined by the subject in selected ways.-C. North America, from the Sierra Nevada to the Rocky mountains, inclusive, will doubtless lead the world in the production of silver and gold for a considerable time. Although the aggregate of the precious metals, hitherto abstracted, reaches an |