6 The Ganoids 
“Tn addition to these, so to speak, purely embryonic char- 
acters there are not a few important adult characters: 
“(z) The continuity of the oviducts with the genital glands. 
‘““(2) The small size of the pancreas, and the presence of 
numerous so-called pancreatic caca. 
(3) The somewhat coiled small intestine. 
‘““(4) Certain characters of the brain, e.g., the large size of 
the cerebellum; the presence of the so-called lobi inferiores 
on the infundibulum, and of tori semi-circulares in the mid- 
brain. 
“In spite of the undoubtedly important list of features to 
which we have just called attention, a list containing not less 
important characters, both embryological and adult, separating 
Lepidosteus from the Teleostei, can be drawn up: 
““(1) The character of the truncus arteriosus. 
“(2) The fact of the genital ducts joining the ureters. 
(3) The presence of vasa efferentia in the male carrying 
the semen from the testes to the kidney, and through the tubules 
of the latter into the kidney-duct. 
““(4) The presence of a well-developed opercular gill. 
(5) The presence of a spiral valve; though this character 
may possibly break down with the extension of our knowledge. 
“(6) The typical Ganoid characters of the thalamencephalon 
and the cerebral hemispheres. 
““(7) The chiasma of the optic nerves. 
“(8) The absence of a pecten, and presence of a vascular 
membrane between the vitreous humor and the retina. 
‘““(g) The opisthoccelous form of the vertebre. 
““(1o) The articulation of the ventral parts of the hamal 
arches of the tail with the processes of the vertebral column. 
“(r1) The absence of a division of the muscles into dorso- 
lateral and ventro-lateral divisions. 
(12) The complete segmentation of the ovum. 
“The list just given appears to us sufficient to demonstrate 
that Lepidosteus cannot be classed with the Teleostei; and we 
hold that Miuller’s view is correct, according to which Lepi- 
dosteus is a true Ganoid. 
“The existence of the Ganoids as a distinct group has, how- 
ever, recently been challenged by so distinguished an ichthy- 
