126 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
IV. Admitting the Marsipobranchi to have had a 
gnathostomous ancestry, it 1s next incumbent to enquire 
with which of the living fishes they are most nearly 
allied. 
I have elsewhere* attempted to homologize the pori 
genitales of the Marsipobranchu with the corresponding 
structures of the females of certain bony fishes in which 
the genital ducts have disappeared; and have pointed out 
that the urinogenital system of the Lampreys and Hags 
may be most satisfactorily compared with that of the 
Teleostei, the characteristic features in the two being an 
entire absence of all connection between the testis and 
kidney (euthorchidic condition) and the more or less 
complete suppression of the genital ducts, such as occur 
in no other living vertebrata. I have been further led to 
consider the genital ducts in both sexes of the Teleostei 
as distinct swi generis from those of the remaining gnath- 
ostomata, and to regard the urinogenital system of Tele- 
osteans and Marsipobranchs as the least modified survivals 
of an hermaphroditic apparatus possessed by the ancestors 
of the vertebrata.+ 
* Jour. Linn. Soe. Lond. Zool., vol. XXIII, p. 551 et seq. 
+ Apropos of Cunningham’s original observations (Qu. Jour. Micr. Sci., 
vol. XXVII, n.s., p. 49) on hermaphroditism in the Hag (Myzine glutinosa), 
Retzius, in criticizing the same, has pointed out (Biol. Forening. Forhandlg. 
Stockholm, Bd. I, p. 25, 1888) after the systematic examination of hundreds 
of examples, that the truly hermaphoditic nature of the individual had not 
been fully established. Cunningham has ina recent paper described the 
movements of the spermatozoa (Qu. Jour. Micr. Sci., N.S., vol. XXXITII, 
p. 173), and with this the enquiry enters the experimental stage. He con- 
fesses (p. 170) to a failure to procure fertilized ova. As he makes no mention, 
either in the paper cited or in its immediate predecessor (Zool. Anz. 1891, 
p. 22) of Retzius’ observations, in must be assumed that he overlooked them. 
This is the more unfortunate, as the most important of.them deal with 
the structure of the encapsulated ovum when apparently nearing extrusion, 
and would unmistakably have been of immediate service to him in his enquiry. 
