No. 375.] REVIEWS OF RECENT LITERATURE. 207 
unequal, and the process of gastrulation recalls that of the urodeles 
and cyclostomes. From the egg there hatches a tadpole which 
develops external gills and a very large sucker of the amphibian 
type. Both suckers and external gills disappear in about six weeks 
after hatching, but not until ten or twelve weeks does the larva feed 
for itself, living up to that time upon the yolk. During the breeding 
season the papillz on the hind limbs of the male grow out into long 
blood-red filaments, apparently ornamental in nature. In the night 
the normally dark color of these animals changes to nearly white, 
the black chromatophores being retracted in darkness. In the dry 
season Lepidosiren behaves much like Protopterus, retreating into 
the mud and breathing by means of an air hole. 
From this brief outline it would appear that Lepidosiren presents 
considerable similarity in its development to Ceratodus, as made 
known to us by the investigations of Semon.! The eggs in this form 
measure 6.5—7 mm. in diameter ; segmentation and gastrulation are 
much the same, but in Ceratodus the envelope is gelatinous, while 
neither suckers nor external gills are developed. The similarities of 
both of these dipnoans to the Amphibia in their external develop- 
ment is very striking, but this does not of necessity imply any close 
relationship between the two groups. One recalls in this connection 
the larval forms of Lepidosteus, as described by Agassiz, and of 
Amia, as figured by Allis and by Dean. 
Fishes of the Vicinity of New York City.— Mr. Eugene Smith 
has just published an excellent list of “the fishes of the fresh and 
brackish waters in the vicinity of New York City ” in the Proceedings 
of the Linnean Society of New York. : 
The list comprises 61 species, 24 being native fresh-water species, 
11 introduced species, and 26 belonging to brackish waters or run- 
ning up the rivers to spawn. The list is accompanied by brief but 
accurate descriptions and by useful notes on the local distribution. 
The work is neatly and correctly done, and should be followed by an 
equally exact list of the marine fishes of the same region. Curiously 
enough, our knowledge of the local fish fauna of New York Bay is 
still incomplete. D. S.J. 
1 Jena. Denkschriften, Bd. iv, 1893. 
