:si.] THE GENEALOGY OF ANIMALS. 881 



single nasal aperture ; and Amphirhina, comprising the 

 other Vertebrata, which have two nasal apertures. These 

 are further subdivided into Anamnia (Pisces, Dipnemta, 

 Amphibia) and Amniota (Reptilia, Aves, Mammalia). 

 This classification undoubtedly expresses many of the 

 most important facts in vertebrate structure in a clear 

 and compendious way ; whether it is the best that can 

 be adopted remains to be seen. 



With much reason the Lemurs are removed altogether 

 from the Primates, under the name of Prosimice. But 

 I am surprised to find the Sirenia left in one group 

 with the Cetacea, and the Plesiosauria with the Ichihyo- 

 sauria ; the ordinal distinctness of these having, to my 

 mind, been long since fully established. 



V. In Professor Haeckel s speculations on Phylogeny, 

 or the genealogy of animal forms, there is much that is 

 profoundly interesting, and his suggestions are always 

 supported by sound knowledge and great ingenuity. 

 Whether one agrees or disagrees with him, one feels that 

 he has forced the mind into lines of thought in which it 

 is tmore profitable to go wrong than to stand still. 



To put his views into a few words, he conceives that 

 all forms of life originally commenced as Monera, or 

 simple particles of protoplasm ; and that these Monera 

 originated from not-living matter. Some of the Monera 

 acquired tendencies towards the Protistic, others towards 

 the Vegetal, and others towards the Animal modes of 

 life. The last became animal Monera. Some of the 

 animal Monera acquired a nucleus, and became amoeba- 

 like creatures ; and, out of certain of these, ciliated 

 infusorium-like animals were developed. These became 

 modified into two stirpes : A, that of the worms ; and 

 B, that of the sponges. The latter by progressive modi 

 fication gave rise to all the Ccelenterata ; the former 

 to all other animals. But A soon broke up into two 



