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stem its cavity is enlarged, and on that enlargement hangs a circle of covering scales not unlike what exist in the genus of Siphonophores, called Physophora. The larva is now in a condition structurally not very distant from the adult. In minor details there are, as has been already pointed out, certain differences, but from this stage on the growth into the adult is direct and without the formation of provisional organs of any kind.
A description of the development from the bud of each kind of characteristic structure found on the stem of the Agalma, would take me into details too special for this paper. It is sufficient for our argument as to the nature of the Agalma, to state that each and every structure along the stem originates as a simple bud, which can at first hardly be distinguished one from the other,
Fig. 10.--Lizzia octopunctata (young). whether they form float, swimming-bell, feeding polyp or covering scale. In their earlier stages they are all alike. The details of the changes by which now a swimming-bell and now a float is formed are not necessary for my argument, and I will not consider them in this place.
I have already, in my former sketch of the anatomy of Agalma, made the comparison of the Siphonophore to a little medusa, called Lizzia, found in our waters. That comparison at which McCrady hinted long ago is supported by the embryology which I have just given.
In the primitive medusa, as has been shown, we find a jellyfish with parts identical with those of a Lizzia. All the organs are duplicated in one and the other. What are the changes of form which in subsequent growth so alter the external form as to produce in the one case a Lizzia, such as I figure (Fig. 10), and in the other an Agalma ?
In the figure of Lizzin octopunctata Forbes (grata Alex. Agassiz), a species common in Massachusetts bay, several buds can be seen through the bell, forming on what is known as the proboscis. If these buds are closely examined, it will be found that they are young Lizziæ in different stages of growth, and if the proboscis of the largest of these buds be minutely studied, on it will be found buds of still a third generation, grandchildren of the original jelly fish. All these buds whether products of the first or second budding process, eventually break away from the place from which they first formed as buds, and swim away as jelly fishes, the form of which is not unlike the parent from which they sprung. Even before that separation takes place, the impatient young may be seen opening and shutting their bells, and swinging on their fragile stems trying to break themselves loose.
Suppose now that the proboscis of the Lizzia from which the buds formed was very much elongated into a tube. This tube then we liken to the axis of an Agalma, and if buds were formed along its whole length, as can be very easily imagined, the likeness would be even more striking. To be sure all the different buds in the Agalma are not of the same form or outline. Neither are they alike in the Lizzia. Some are very fully grown while others are in incipient stages of growth. This variety in shape could not then be an objection to the comparison which I have urged.
Each bud which forms along the stem of an Agalma is called by some naturalists an individual, from the fact that in early stages they resemble each other so closely, and when fullygrown oftentimes certain of them bear such a close likeness to forms of Medusæ, which lead an independent life. I do not consider every bud an individual, but think that in some cases the position on the stem or other causes has so modified them that two or even more buds, as in the case of polypite, and covering scale together make one true individual. A zooid, as defined by zoologists, does not seem to be a fitting term to apply to these structures found along the axis of an Agalma, unless the term be given the broadest extension. In such a case the distinction between a zoöid and an individual does not seem very great. Through those jelly fishes called the Trachynemidæ, as Circe, there seems to be a close relationship between the hydroid Medusa, Lizzia, and the common Aurelia, Cyanea and other Discophoræ. As therefore I cannot but designate a Pelagia, also a Discophore, as an individual, I must look upon a Circe as the same, and since Lizzia and Circe are closely related, their free Medusæ are likewise morphological individuals. If this is true, and our theory of the likeness between Agalma and Lizzia not fanciful, is it proper to call the members of the former colony zoöids, or shall we regard them true individuals ?
The solution of this problem as to the exact nature of the members of an Agalma colony is most difficult, and, as so many before me, I must leave this speculative part of my subject with the trite remark, that in this animal we have a condition of life where the difference between organ and individual is reduced to a minimum. It is without doubt true that much of the controversy which has been indulged in, as to the exact nature of the different components of the Agalma, may reduce itself to a quarrel about terms.
THE RELATION OF APICULTURE TO SCIENCE.1
BY A. J. COOK.
there is no better student of American agriculture, remark, that the art of agriculture was founded almost wholly upon empiricism ; and that all it had to thank science for, was that the latter explained what had already been determined by the empiric method. Whether this be true or not, the reverse is most certainly true of practical entomology. Economic entomology rests almost wholly upon science. So, too, apiculture, as practiced to-day, owes its very existence to science. Fear deters most people from bee-keeping, unless a desire to study bees, and to know more of the nature and habits of these marvels of nature, impels to that close association with bees, which practical apiculture demands.
For this reason, there is no class of men engaged in manual labor pursuits which possesses the intelligence and enthusiasm which characterize apiarists, or which practices so much that is really scientific. The successful apiarist of to-day must be able to inspect every part of his hives; must be constantly familiar with the precise condition of every colony of his bees; must be possessed of quick and accurate powers of observation. Thus we understand why science has gleaned so much from practical apiculture.
1 Read before the Entomological Section of the A. A. A. of S.
The nature of the several bees in each colony, as to sex, function and longevity, is now well known to every intelligent apiarist. The peculiar characteristics of queen, drones, and workers, and the peculiar duties of workers of different ages, are matters of daily observation.
The queen is seen to lay three or four eggs per minute, and the apiarist, by adding comb with empty cells, proves that she may lay as many as 4000 eggs per day. Aristotle was correct, then, in calling the queen the mother, and Virgil wrong in pronouncing her to be the king. Her hatred of rivals is easily shown by the certain combat, fatal to one of them, when two queens are placed together. This enmity induces swarming, as bees rarely suffer a plurality of queens in the same hive. In swarming the queen never leads, yet the special place of clustering is usually determined hy the queen. Unless the queen accompanies the swarm, the latter will always return to the hive.
By clipping one wing of a virgin queen, so that flight will ever after be impossible, the bee-keeper quickly proves the correctness of the great Huber's discovery, that queens always mate on the wing. The same experiment proves the correctness of Dzierzon's more wonderful discovery, that drone bees are a result of agamic reproduction. No queen whose wing is clipped while yet a virgin, so far as I have observed, and I have tried the experiment many times, will ever lay eggs that will produce other than drone bees. It is also true that if a queen is forced to virginity for three or four weeks, she will always remain a virgin.
Upon the queen's return from her mating flight, we may observe the evidence of success, as she always if successful bears away a portion of the drone's reproductive organs, which remain attached to the queen for some hours.
It was a theory of the late Samuel Wagner, that the placing of unimpregnated eggs in the larger cells of the drone comb, and the impregnated ones, in the smaller worker cells, was simply automatic. The pressure from the smaller cell upon the queen's abdomen, forced the sperm cells from the spermatheca, as the eggs passed by. As there would be no such pressure from the larger drone cells, the spermatozoa would not be extruded from the spermatheca. Practical bee-keepers have shown this to be untrue.
Queens have been seen to lay eggs in the still larger queen cells, which eggs are always impregnated. The queen often lays in worker cells, where the walls are but just commenced, and where there is no compression; yet such eggs are always impregnated. That the bringing of the sperm cells into connection with the germ cells, or the withholding of them, as the eggs are to produce females or males, is a matter of volition with the queen, iş sustained by the muscular character of the spermatheca. It is a curious fact, that young queens, when they first commence to lay, often put several drone eggs into worker cells, though after the first day or two, they generally deposit only impregnated eggs for the first season. It seems probable, that the muscles of the seminal sack of the queen do not act efficiently till somewhat in practice,
An anomalous physiological fact is illustrated in the flight of the queen when swarming takes place. Though she may not have used her wings since her marriage flight, possibly for two or more years, yet the muscles are by no means atrophied, as shown by her rapid flight, often for several miles, en route to her future home.
The reason why a few impregnated eggs develop into queens, while thousands of the same produce worker bees, appears to be wholly due to quality and quantity of food. They receive much more and much richer food. The enlarged cell is necessary to a full sized queen, but not to a queen. The exceptional position of queen cells is simply for convenience, as it is not important.
Direct observation, as also her removal from the hive, shows that the only function of the queen is to lay eggs.
I have known a queen to lay with no abatement of fertility for five years, though often in one or two years she ceases to be prolific, either from her own impotency, or from a depletion of the spermatheca, in which case only drone bees are produced. Usually the worker bees arrange to supercede the queen before she becomes an exclusive drone producer.
Common observation proves that the drones are males, that they are great eaters, and that they have no function in the