14 



SCIENCE. 



HUNGER THE PRIMITIVE DESIRE. 

 By S. V. Clevenger, M. D. 



A paper on Researches into the Life History of the 

 Monads by W. H. Dallinger, F. R. M. S., and J. Drysdale, 

 M. D., was read before the Royal Micrscopical Society, 

 Dec. 3d, 1873, wherein fission of the Monad was de- 

 • scribed as being preceded by the absorption of one form 

 by another. One Monad would fix on the sarcode of an- 

 other and the substance of the lesser or under one would 

 pass into the upper one. In about two hours the merest 

 trace of the lower one was left and in four hours fission 

 and multiplication of the larger monad began. A full 

 description of this interesting phenomenon may be found 

 in the Monthly Microscopical Journal (London), for 

 October, 1877. 



Professor Leidy has asserted that the Amoeba is a can- 

 nibal, whereupon Mr. J. Michels in the American Jour- 

 nal of Microscopy, July, 1877, calls attention to Dallin- 

 ger and Drysdale's contribution and draws therefrom the 

 inference that each cannibalistic act of the Amoeba is a 

 reproductive one, or copulative, if the term is admissible, 

 The editor (Dr. Henry Lawson), of the English journal, 

 Oct., 1877, agrees with Michels. 



Among the numerous speculations upon the origin of 

 the sexual appetite, such as Maudsley's altruistic conclu- 

 sion, which always seemed tome to be far-fetched, I have 

 encountered none that referred its derivation to hunger. 

 At first glance such a suggestion seems ludicrous enough, 

 but a little consideration will show that in thus fusing 

 two desires we have still to get at the meaning and deri- 

 vation of the primary one — desire for food. 



The cannibalistic Amoeba may, as Dallinger's Monad 

 certainly does, impregnate itself by eating its own kind, 

 and we have innumerable instances among Alga; and 

 Protozoa of this sexual fusion appearing very much like 

 ingestion. Crabs have been seen to confuse the two de- 

 sires by actually eating portions of each other while cop- 

 ulating, and in a recent number of the Scientific Ameri- 

 can, a Texan details the Mantis religiosa female eating 

 off the head of the male Mantis during conjugation. Some 

 of the female Arachnida? find it necessary to finish the 

 marital repast by devouring the male, who tries to scam- 

 per away trom his late. The bitings and even the em- 

 brace of the higher animals appears to have reference to 

 this derivation. It is a physiological fact that association 

 often transfers an instinct in an apparently outrageous 

 manner. With quadrupeds it is undoubtedly olfaction 

 that is most closely related to sexual desire and its re- 

 flexes, but not so in man. Ferrier diligently searches the 

 region of the temporal lobe near its connection with the 

 olfactory nerve for the seat of sexuality, but with the di- 

 minished importance of the smelling sense in man the 

 faculty of sight has grown tovicarate olfaction ; certainly 

 the "lust of the eyes" is greater than that of other spe- 

 cial sense organs among Bimana. 



In all animal life multiplication proceeds from growth, 

 and until a certain stage of growth, puberty, is reached', 

 reproduction does not occur. The complementary nature 

 of growth and reproduction is observable in the large 

 size attained by some animals after castration. Could 

 we stop the division of an Amoeba a comparable increase 

 in size would be effected. The gro'.esqueness of these 

 views is due to their novelty, not to their being unjustifi- 

 able. 



While it would thus seem apparent that a primeval 

 origin for both ingestive and sexual desire existed, and 

 that each is a true hunger, the one being repressible and 

 in higher animal life be ng subjected to more control than 

 the other, the question then presents itself: What is 

 hunger? It requires but little reflection to convince one 

 of its potency in determining the destinies of nations and 

 individuals, and what a stimulus it is in animated crea- 

 tion. It seems likely that it has its origin in the atomic 



affinities of inanimate nature, a view monistic enough to 

 please Haeckel and Tyndall. 



NOTES ON THE ANATOMY OF THE ENCE- 

 PHALON, NOTABLY OF THE GREAT GAN- 

 GLIA. 



By Edward C. SprTZKA, M. D. 



The anatomy of no portion of the brain is so obscure 

 and so imperfectly known as that of th*e so-called Thala- 

 mus opticus. One of the first requisites to a comprehen- 

 sion of its relations is the establishment of a proper 

 nomenclature, and the point to start from is the very 

 name under which the great ganglionic mass is known. 

 Since it is not exclusively or even in the main connected 

 with the optic tracts in any animal or man, and, indeed, 

 is in the lower sauropsidas and amphibians not connected 

 with them at all, the affix opticus should be dropped, and 

 the first word involving that very uncompromising con- 

 ception of an elevation at the ventricular floor may be 

 retained : Thalamus. 



The current conception that the Thalamus is an eleva- 

 tion at the floor of the lateral ventricle is incorrect. One 

 of our leading comparative anatomists will shortly review 

 this question, and it will therefore be but necessary for 

 •me to refer to the matter. 



In the cat's brain it can be clearly seen, that (aside 

 from membranous separations) the great mass of the 

 Thalamus is excluded from the cavity of the lateral ven- 

 tricle by the fusion of the lateral edge of the fornix with 

 the corpus striatum, or rather with the ependyma of that 

 ganglion. Consequently, the twothalami are included in 

 the third ventricle, which cavity on cross section resembles 

 an upright T, whose vertical branch descends between 

 the thalami, as a deep ditch, the vulva cerebri of the old 

 anatomists. 1 



Luys, who was unfortunately wedded to certain physi- 

 ological prejudices as to the function of the thalamic cen- 

 tres, restricted the term Thalamus to the most external 

 mass. Meynert called all the centres in the aggregate by 

 that term as a collective designation. He excluded, 

 however, that gray mass which lines the sides of the ver- 

 tical slit of the third ventricle. • 



Now, the third ventricle, as shown by Hadlich and 

 Wilder, extends over the entire thalami ; it would be, 

 therefore, incorrect to limit the designation *' central 

 tubular gray of the third ventricle " to that portion only 

 which lines the vertical slit. Either this latter designa- 

 tion should be extended to the entire thalamic masses or 

 the term thalamus should be extended to the so-called 

 central tubular gray. 



Thus interpreted there would be, strictly speaking, but 

 a single thalamus, consisting of two main masses, and a 

 commissural part. The commissure is double. The 

 thalami are primitively united by the lower of these com- 

 missures, which I propose to term " basilar commis- 

 sure." 2 Secondarily, and only in animals above marsu- 

 pials (as far as I am aware), do we find another commis- 

 sure produced at an advanced period of embryonic de- 

 velopment by apposition of the main masses. This is the 

 so-called middle commissure of the brain, the commissura 

 grisea, c. mollis. I should consider the least ambiguous 

 designation, " the thalamic fusion." 



In a manner similar to that which separates the can- 

 date and lenticular nuclei from each other, and which 

 divides the latter into subsidiary "articuli," the chief 

 mass of each thalamus is separated into an inner and 

 outer zone. The zones are separated from each other by 



^he corresponding penis cerebri of the same anatomists has, by more 

 fastidious colleagues, been rebaptized pin US cerebri and later /lineai 

 gland , now known as the epiphysis cerebri. 



'■'Continuous in front with the loci per forati antici, behind with the in- 

 fundibulum. Atrophic over the chiasm, it exhibits a set of transverse 

 fibres and gray substance elsewhere. 



