1894.] ; Lepidosirenids and Bdellostomids. 581 
LEPIDOSIRENIDS AND BDELLOSTOMIDS. 
By THEODORE GILL. 
I. 
In the American NaruRALIST for November, 1893, Dr. 
Howard Ayers has published an article “ on the genera of the 
Dipnoi Dipneumones” which exhibits a characteristic—“ lump- 
ing "—which, may sometimes be a virtue but which, in this 
particular instance, has been exaggerated into a decided fault. 
In 1885, Dr. Ayers created much astonishment among nav- 
uralists familiar with the history of the Lepidosirenids by not 
only refusing to admit the generic differentiation of Lepidosi- 
ren and Protopterus, but by contending that the representatives 
of the two genera were even specifically inseparable, and that 
the American habitat of the type was doubtful ! 
In the article just cited, Dr. Ayers has given a reluctant and 
grudging admission to specific rank of the two types but has 
unqualifiedly denied their higher rank; grudgingly, because 
he concludes that “if they had to be named as new discover- 
ies to-day, and could be studied together in so doing, most 
zoologists would include both animals in one genus, even if they 
did not group them as varieties of one species” (p. cit., p. 922). 
Dr. Ayers’ former article has been sufficiently answered by 
Baur, Schneider, and Parker, and his last article fails to inval- 
idate their contentions. I shall only add that, after a compar- 
ison of the entire body as well as the skeleton of Protopterus 
annectens with the descriptions and figures of the corresponding 
parts of Lepidosiren paradoxa, I am convinced that no zoologist 
of mature experience would hesitate to rank Lepidosiren and 
Protopterus as very distinct genera.’ - 
1Professor Ray Lankester, in ** Nature" for April 12, 1894, (p. 555), has an- 
nounced that he recently obtained, “by purchase from a London dealer, speci- 
mens of the Lepidosiren of the Amazon well preserved in spirit" (how many he 
has not told). He has illustrated peculiarities in “the limbs of Lepidosiren par- 
adoxa,” and we may soon expect more details from that accomplished naturalist. 
