70 ON THE APPENDICES GENITALIAS (CLASPERSl IN THE SELACHIANS. 



7 cm 



r cm 



made thicker and, towards the end, enlarged in a clavate manner, when compared with the medial 

 one; the lateral branch in particular is often distally much swollen. The dermal teeth are fine, a little 

 bent thorns, all with the points forward, towards the base of the organ. The lateral branch does not 

 contribute to the bordering of the appendix-slit of the terminal part, this slit running only between 

 the medial and the dorsal branch 1 )- 



In three specimens of the respective length of 78™, 77"", and 7o cm , the measures were: 



The length of the appendix from the fore edge of the cloaca 7,5 cm , io,5 cm , 6,5°™ 



The free part of the shaft 2,3"", 2,6 cm , 2,3"" 



The terminal part 4,5 cm , 6 cm , 4,1™ 



The breadth (on the broadest part of the shaft) i,i cm , i,6 cm , i,i ci " 



The breadth (on the middle) of the terminal part o,7 cm , i,i cm , o,7 c 



The pelvic copulatory appendage has in all three specimens a length of . 2,i c 



a breadth of o,6 cm . 



In one pair of ventrals, kept in spirit, and skeletonized until the terminal part, belonging to a 

 specimen the total length of which I am not able to give, the appendix has had a length of more 

 than 9 cm , the terminal part of almost 6 cm by a breadth on the middle of i cm , at the end of 1,5°'"; the 

 skeletonized pelvic appendage is 2 cm long, and i ct " broad. 



The skeleton. The pelvic arch is divided in the middle line, so that it is composed of a 

 right and a left piece; behind, dorsally above the articulation with the ventral, each of these pieces 

 is prolonged to a considerable process; on the foremost convex edge the peculiar, movable, foremost 

 copulatory appendage, the Sageplatte (Gbr.), is articulated; the skeleton of this appendage is com- 

 posed of one piece, the medial edge of which bears a row of (5 — 7) large, crooked, finely pointed 

 dermal teeth; when in rest this piece is turned against the ventral surface of the pelvis which is 

 hollowed like a spoon, and then onlv the toothless edge laterally of the row of teeth is seen in the 

 opening of the pouch. 



The fin-stem consists of a short, flat b as ale B bearing all the rays (the foremost broad mar- 

 ginal ray (R) is coalesced with it), a 6 I} a good-sized /?, and the appendix-stem b 2 ). 



b t is not much shorter than the basale, with which it is connected in a rather movable joint; 

 on its medial side it is flat and broad, on the lateral side longitudinally concave; dorsally it forms a 

 narrow edge, forward produced into a large process x, which by a lateral incision is made to form 

 the inner bordering of the above mentioned opening, with which the appendix-slit begins; the other 

 part of the dorsal edge of b l is somewhat laterally bent, and bears a rather firm margin of connective 

 tissue; the ventral edge is straight and rounded. 



The piece /? is tolerably triangular, but with curved sides; it is much curved, and situated in 



') In Chimcera affhiis Cap. the appendices, according to Goode & Bean (I.e. pi. X, fig. 34, 35), are three-branched 

 as in (.h. monstrosa, but else they seem to differ rather much from those of this latter. The figures, however, are not distinct 

 enough t< » get a clear notion of the facts. 



-) In the figures of Gegenbaur I.e. pi. XVI, fig. 22, 23, and of v. Davidoff, I.e. pi. XXIX, fig. 19, pi. XXVIII, 



1, these skeletal pieces are marked in such a way that: i, = [ b Gbn , B = ['' Gbn , i = f ij Gbn 



» c D. \c 3 D. ( c 2 D. 



