330 MR. J. 8. BUDGETT ON SOME POINTS IN 
view which was latterly held by Balfour that primitively the testis had a duct of its 
own, derived either from a Miillerian duct like that of the female Elasmobranch, 
or a structure swi generis, as held by Howes and Max Weber, and that, on the other 
hand, the connection of the testis with the tubules of the kidney found in the male 
Elasmobranch, Amphibian, and Amniot is a secondary one. 
There is, however, a difficulty with regard to the latter view in the fact that 
Lepidosteus, the Ganoid fish which, as regards its ovary and oviduct, most closely 
resembles the Teleostean arrangement, in having a closed ovary. continuous with its duct, 
is the very one which shows this supposed secondary connection of testis with kidney. 
It is possible, however, that this acquirement is confined to Lepidosteus, while 
other Ganoids retain the primitive condition; and it may be that it is a feature which 
has been frequently acquired independently. So that the Elasmobranch, Amphibian, 
and Amniot are not necessarily a separate evolutionary line from the Crossopterygian, 
Dipnoon, Ganoid, and Teleost, but the Amphibia may have acquired the Elasmobranch 
arrangement after they split off from the Dipnoi, which have not acquired it. 
That the arrangement in Lepidosteus is not primitive seems probable from the fact 
that the testis-tubules open into a well-marked longitudinal collecting-duct, which 
lies along the ureter in the same position as the testis-duct in Polypterus, and it is 
from this longitudinal duct that the transverse tubules pass to the kidney. 
That the arrangement in Polypterus is not secondary seems probable from the fact 
that not only is it the simpler method of conveying the testis-products outwards, but 
is, on the whole, closely similar to the arrangement in the female Polypterus, and we 
can hardly suppose that in the primitive vertebrate the ova and spermatozoa found 
exit by totally different means. 
VII. Abdominal Pores. 
In both male and female, abdominal pores are present in Polypterus. ‘They have 
been correctly described in the adult as fine canals opening to the exterior on either 
side of the vent (Pl. L. figs. 7,8). In the young female 9 cm. in length there is a very 
fine nucleated diaphragm cutting off the communication of the coelom with the exterior. 
This is, however, extremely delicate (Pl. L. fig. 9, ab.p.). 
In the young male 9 cm. in length the ceelom is completely shut off from the 
exterior, the abdominal pores not being yet formed. 
VIII. The Anal Fin. 
Traquair has already noted in Calamoichthys that the males have an enlarged anal fin. 
In Polypterus, during the breeding-season at least, this difference is not merely one of 
size but also of shape and form, as shown in PI. L., figs. 1 & 2. 
The anal fin in the female is narrow and pointed, while in the male it is twice as 
deep as in the female, and its surface is thrown into deep folds between the successive 
