THE SOCIETY^S NOTE-BOOKS. 6lf 



Blood of Congo Snake.— The so-called "Congo Snake" — 

 Amphiuma — is a native of North America. It is not really a 

 snake, nor even a reptile at all, but an amphibian. 



The Amphibia, which, together with the fishes, form in modern 

 zoological classification the division Ichthyopsida of the Vertebrate 

 sub-kingdom, differ from the reptiles in the possession of gills in 

 the early stages of development, or through life ; in the skin 

 being naked instead of being covered with scales, and in several 

 other points of anatomy and development ; in all of which, except 

 the absence of scales, they agree with the fishes. They are 

 divided into four orders, of which one, Lahyrinthodo7ita^ has been 

 extinct since the period of the Lias ; and another, Cceciliidce^ 

 includes only a few tropical slow-worm-like creatures. Of the 

 other orders, that of the Afioura, or tailless amphibians, includes 

 the frogs and toads ; the remaining order, Urodela^ or tailed 

 amphibians, is divided into two sections : Caducibranchiaia^ in 

 which — e.g.^ our common newts — the gills disappear in mature life, 

 respiration being carried on by the lungs alone ; and Perennibran- 

 chiata, as the Axololi, in which the gills are persistent throughout 

 life. The latter thus permanently resemble the larva or tadpole 

 stage of the newts. It has, however, been recently discovered 

 that certain amphibians which ordinarily are aquatic in their 

 habits, and retain their gills through life, breeding while in that 

 state, nevertheless, if kept in confinement, lose their gills, and 

 come to resemble land salamanders. Amphiuma is intermediate 

 in a different way, for although its gills disappear when adult, the 

 gill-clefts behind the head remain through life. The blood cor- 

 puscles in Amphibia are oval and nucleated ; they are very large, 

 especially in the Perennibranchiata^ being large enough to be 

 visible to the naked eye in several species — e.g.^ in Proteus atiguinus^ 

 a curious blind animal inhabiting the underground lakes in 

 certain large caves in Austria. It is, however, in Amphiuma that 

 the blood corpuscles reach the maximum size met with in any 

 vertebrate animal, those of the Musk Deer being the smallest. 

 The spermatozoa of AmpJiiuma are also very large and peculiar 

 in shape ; they are described and figured in, I believe, one of 

 the numbers of the " Popular Science Review" for 1875 or 1876. 



H. P^RANKLiN Parsons, 



Sebaceous Glands of the Ear.— Although there are Sebaceous 

 glands in the hair-follicles of the external meatus, the cerumen is 

 really a secretion of S2veat-glands. The small racemose sebaceous 

 glands of the skin open nearly always into hair-follicles ; but the 

 follicles are in many places so small as to appear to be simply 

 lateral involutions of the excretory duct of the gland. The 



