28 [Feb. 



find such an arrangement. Generally I found them situated on one side of a nerve 

 projecting from the bundle of nerve tubules and enveloped in the same sheath, 

 but in several instances I found them separating, or situated between several of 

 the nerve tubes, the tubes so separated, after passing the bodies, resuming their 

 position along with the others. Besides being invested by the nervous sheath, 

 they are more closely held in connection with the nerve by means of transverse 

 fibres of white fibrous tissue. After having thus discovered and examined these 

 curious bodies in the Boa, I expected to find the same in other serpents, and ' 

 I accordingly obtained a Coluber constrictor and Leptophis sauritus, into which I 

 carried my comparative researches, but without finding the least trace of a 

 similar or analogous structure. From their absence in these two serpents, it 

 occurred to my mind that they might be the ova of entozoa — but the entire struc- 

 ture precludes any idea of this kind — and although they have several of the most 

 important elements of structure of the Pacinian corpuscle, yet they have no nerve, 

 of which as a conductor, ifwe consider the Pacinian corpuscle in any way the centre 

 of any kind of nervous or other power, must be considered as a sine qua non ; but 

 if a mere filament of distribution, it would be comparatively of little importance, 

 and the close apposition of the bodies with the nerves in the Boa, might possibly 

 answer the same purpose. But if they are of the nature of the Pacinian corpuscle, 

 why not exist in all serpents ? In this maze of perplexity, I present these observa- 

 tions to the Academy, and hope that future researches will throw some light upon 

 the subject. 



Before finishing with these remarks, it may be important for me to state that I 

 saw none of these bodies in any other situation in the Boa, than along the nerves 

 mentioned, although I examined all other parts carefully, excepting the viscera 



and their attachments. 



Explanation of the Figtires. 



Fig. 1. Represents a portion of an intercostal nerve of the Boa constrictor, 

 with the sheath removed, and exhibiting five of the bodies which resemble the 

 Pacinian corpuscle, acted upon by dilute acetic acid, and highly magnified. The 

 upper three bodies on the left side, it will be observed, have separated some of 

 the nerve tubules from the main body of the nerve; a. Central mass of granular 

 substance ; h. external investing capsules ; c. nuclei of the capsules. 



Fig. 2. Represents a portion of a nerve, with the sheath removed from one 

 side, and one of the "bodies " with the sheath remaining upon the other side, 

 acted on by dilute acetic acid, and more highly magnified than Fig. I. a. nervi 

 tubuli ; b. fibrous sheath of the nerve ; c. several primitive nuclei of the fibrous 

 element of the sheath; d. one of the "bodies"; e. central granular mass; /. ex- 

 ternal investing capsules ; g. nuclei of the capsules. 



Fig. 3. Represents a portion of several of the capsules very highly magnified 

 so as to exhibit the structure of the nuclei, a. capsules; b. nuclei. 



Fig. 4. Represents the eye of Balanus rugosus, much magnified, a. optic 

 nerve ; c vitreous body. 



William E. Whitman, Esq., John Jay Smith, Esq., William R. 

 Lejee, Esq., Henrj^ C. Lea, Esq., and Francis F. Wolgemuth, Esq., all 

 of Philadelphia, were elected Members, zxxA the following were elected 

 Corresponde7its : 



Rev. William Scoresby, D. D., of England. 



Jean Jaq. Kaup, of Darmstadt. 



