436 



SCIENCE 



[N. S. Vol. XXXIX. No. 1003 



The Morphology of the Pectoral Spine and Gland 

 in Certain Cat fishes: H. D. Reed. (With dem- 

 onstration.) 



The Innervation of the Integument of Chiroptera: 

 J. E. ACKERT. (With lantern slides.) (Intro- 

 duced by Robert K. Nabours.) 

 The integument of Myotis lucifugus (LeConte) 

 and M. sublatus (Say), stained intra vitam with 

 methylene blue, reveals a number of nervous struc- 

 tures. Among them are free nerve terminations 

 which can be seen most readily ia the flying and 

 interfemoral membranes, and which, so far as the 

 writer has been able to ascertain, have not been re- 

 ported heretofore in these organs. 



Nerves end on pelage hairs at three levels and 

 in three different sheaths of the follicles. These 

 endings are: (1) a superficial nerve ring situated 

 ectad of the orifices of the sebaceous glands, and 

 giving off nerve threads in the connective tissue 

 sheath; (2) fine, varicose or flattened nerve fibrils 

 lying immediately entad of the openings of the 

 sebaceous glands, and terminating on the hyaline 

 membrane parallel to the long axis of the hair; 

 (3) nerve fibrils at the level of the lower third of 

 the follicle, usually taking a horizontal position in 

 the outer root sheath. Apparently, nerve endings 

 similar to the last type have not been described 

 previously in the hair of the bat. 



The skin contains two kinds of special sensory 

 end-organs: (1) a small, elongate end-iuTb into 

 which a single medullated nerve fiber enters, ex- 

 tends approximately to the opposite end, and ter- 

 minates in a slight enlargement; (2) a large, 

 round, cellular terminal corpuscle innervated by a 

 single fiber which disappears among the cells of the 

 organ. Terminal varicosities are abundant in the 

 region of the hairs outside of the follicles. 



In the skin of the face, especially, there are well- 

 developed striated muscles which bear motor end- 

 plates. While some of these plates appear to be 

 beneath the sarcolemma in the integument, they 

 are unquestionably so placed in the muscles of the 

 tongue. 



Of interest are the large, modified sweat glands, 

 some of which have numerous fibrils running 

 about them. In the absence of definite observa- 

 tions on the innervation of sudoriparous glands, it 

 seems possible that these fibrils, which resemble 

 sympathetic post-ganglionic neurites, may form 

 plexuses about the glands similar to intracapsular 

 plexuses around cell bodies of sympathetic 

 neurones. 



Blinded bats when on the wing probably perceive 



obstacles through the sense of touch by the effect 

 of condensations of the atmosphere (produced on 

 approaching the object) upon the free nerve termi- 

 nations in the epidermis and the superficial nerve 

 rings of the hair follicles. 



EMBEYOLOGT 



On the Parallelism Between Increase in Permeabil- 

 ity and Abnormal Development of Fish Eggs: 

 J. F. McClendon. 



The morphology of abnormal Fundulus embryos 

 has been studied by Dr. Stockard. My work has 

 been merely an attempt to find the cause of the 

 abnormalities. 



I found that distilled or sea-water solutions of 

 nicotine and the salts of Na, Li, K, Ca and Mg 

 all produced the same a,bnormalities in the em- 

 bryos. In other words, any one of the above sub- 

 stances produced all of the types of abnormalities 

 when applied to eggs in early cleavage stages. 



If the eggs are placed in distilled water or 

 "balanced" salt solutions no salts diffuse out of 

 them. Only the kations have to be balanced; for 

 example, if eggs are placed in a solution contain- 

 ing nitrates of Na, K, Ca and Mg, no chlorides 

 diffuse out of them. 



But if the eggs are placed in distilled-water so- 

 lutions of any one of these substances, the salts 

 contained in the eggs diffuse out into the solutions 

 and may be detected by ordinary chemical analy- 

 sis. It is thus shown that solutions which cause 

 abnormalities also increase the permeability of the 

 eggs to salts (and perhaps to other substances). 

 Solutions that were too weak or had acted for too 

 short a time to produce abnormalities, had in- 

 creased the permeability of the eggs to a slight 

 degree. Therefore, the increase in permeability 

 seems to be the cause and not an effect of the ab- 

 normal development. 



The Effect of X-rays on the Bate of Cell Division 

 in, the Early Cleavage of Planorbis: A. Rich- 

 ards. 

 An Experimental Study of Concrescence in the 

 Embryo of Cryptobranchus allegheniensis : Ber- 

 tram G. Smith. (Illustrated with lantern 

 slides.) 



By the method of vital staining the following 

 facts concerning the formation of the embryo of 

 Cryptobranchus were established: (1) A band of 

 cells occupying the lateral and ventral parts of the 

 equatorial region of the late blastula, during gas- 

 trulation comes to occupy the corresponding parts 

 of the margin of the yolk plug, and converges on 



