296 Bashford Dean M.emorial Volume 



There is now to be considered the matter of the notch toward the posterior end of the 

 ventral lobe of the caudal fin, a feature common to practically all sharks. Of it Garman 

 says (1885.2, p. 4) "the tail ... fin is not divided into lobes by a notch in its lower 

 border." If the reader will now turn to Carman's figure (our Text-figure 1) he will see 

 why this statement was made. However, in his article on the tail of the unmutilated 

 specimen (1887, P- 267) Garman says nothing of any caudal notch, merely stating that the 

 tail "tapered to a sharp extremity." Furthermore in 1913 (p. 15), in his last description of 

 the tail of Chlamydoselachus, he writes: "Caudal long, pointed, . . . subcaudal deep 

 anteriorly, narrowing backward, not separated by a notch from the tip." In this he agrees 

 with Giinther's figure (our Figure 1, plate I). On the other hand, in CoUett's photograph 

 (our Figure 3, plate I), there is shown what seems to be a notch in the hinder part of the 

 ventral lobe of the caudal. A similar notch (?) is shown in Bolivar's photograph (1907.2, 

 PI. 5), our Figure 4, plate I. However, in both cases this may be wholly or in part the 

 result of rough handling and of drying. 



In the other published figures of Chlamydoselachus, the conditions with regard to 

 the caudal notch may be briefly stated as follows. Doflein's figure, presumably drawn in 

 Japan from a fresh specimen, shows a slightly sinuous tail with no sign of a notch (our 

 Figure 2, plate I). The illustration in Mertens' article (1921), reproduced as Text-figure 4, 

 shows an upwardly bent tail with a drooping tip without a notch. Bertrand's photo- 

 graph (1926) shows a straight tail with a lappet at the tip, which is set off ventrally by a 

 notch as may be seen in our Figure 6, plate II. Lozano Key's (1928) portrayal (reproduced 

 in our Text-figure 6) is almost identical with Giinther's figure (our Figure 1, plate I). 

 Lastly, Ito's drawing (our Text-figure 5) shows a tail without a sign of a notch. 



Examination of our adult specimens gives the following facts. No. I has an almost 

 perfect tail with the point lacking dermal fin-rays and therefore consisting of the hard 

 central part of the tail. It has no notch and is almost a duplicate of the tail of Bertrand's 

 fish (our Figure 5, plate II). In fish No. II, the tip of the tail has been broken and torn 

 (much as in CoUett's specimen), hence we cannot say whether or not it had a notch. No. 

 Ill, our largest specimen, has a very long slender tip about equally "feathered" with 

 dermal fin-rays above and below, somewhat as in Giinther's illustrations (our Plate I, figure 

 1). It has no notch and is very similar to the tail figured by Bolivar (our Figure 4, plate I). 

 The tails of our six embryos show widely differing tips, which will be described in a future 

 article on the embryology of Chlaynydoselachus. 



In all the figures and descriptions of the tail of Chlamydoselachus given above, and 

 in our own material, we find this organ unusually long and tapering. In many specimens 

 it continues the axis of the body nearly straight backward, in others it has a decided up- 

 ward bend as in most sharks. The dorsal lobe is always insignificant in siz;e, the ventral 

 always relatively large. We believe that an upward slant of the tail is the normal position 

 while swimming. This must be the case in order to bring the large ventral lobe into line 

 with the anal fin and with the body to keep the fish on a generally straight course. 



The close association of dorsal, anal and pelvic fins with the caudal, gives the crea- 



