7 6 



ON THE APPENDICES GENITALES (CLASPERS) IN THE SELACHIANS. 



sponds to the Sageplatte^- 1 ) of the Chii>urra\ it is here more lengthened, with a longer shaft' broad- 

 ening in the free end to an obliquely cut off, rather thick plate; this plate is on its (when in the 

 position of rest) ventral surface towards the edge invested with numerous, flat, sharp, comb-shaped 

 dermal teeth, of which those nearest the edge are the largest. Each tooth is almost fan-shaped with 

 the edge divided into 5 — 7 pointed comb-teeth, of which the middle one is the largest (comp. Dume- 

 ril I.e. pi. 14, fig. 2, 2 a). The teeth continue, somewhat smaller, along the whole (dorso-) medial edge 

 of the Sageplatte ; they are placed on a dermal lip, which is unsupported by skeleton (and borders 

 the afterwards mentioned canal, into which a sound can be introduced). As far as I can see the teeth 

 continue all the way to the attached base of the organ. The points of all these teeth are turned forward. 

 On the opposite surface (the dorsal one when in the position of rest) this Sageplatte is pro- 

 vided with a rather curiously elaborate system of large dermal folds partly supported by an inner car- 

 tilaginous skeleton 2 ). From the dorsal edge of the organ a large, folded dermal plate projects on 

 either side. 1) The lateral one of these plates somewhat recalls a human ear, and is with its free 

 edge folded towards the dorsal side of the serrated plate ; the proximal part of this membrane is 

 supported by a particular cartilage, while the distal part which is very much folded, has no inner 

 skeleton. 2) Next another dermal leaf arises from the dorsal and lateral surface of the serrated plate , 

 opposite to the former; it is folded the other way, and situated between the serrated plate and 

 the first leaf; it has no skeleton. 3) The second dermal leaf projecting from the serrated plate» 

 towards the medial side, is anteriorly grown fast to the inner wall of the pouch; its free edge 

 is folded in such a manner, that it forms a kind of bag; it contains no skeleton, but where it 

 posteriorly is united with the lateral leaf (1) at the dorsal edge of the serrated plate , these two 

 leaves, by a rolling of their common hindmost part, form a tube supported by a stiff cartilaginous 

 skeleton; the free end of this skeleton projects some way past the end of the serrated plate > (cp. the 

 figure of Dumeril). A sound inserted into this tube, can be brought far into a deep, dorsally open 

 canal along the dorsal edge of the serrated plate ■ ; on the medial side the bordering of this canal is 

 formed by the above mentioned teeth-eovered dermal lip. 4) Finally a big, white, ovate body project- 

 ing from the medial wall of the pouch, is found outside the bag formed by the inner dermal leaf (3). 

 This evidently is a glandular body 3), the opening (or rather openings) of which seem to be inside 

 the bag formed by the inner leaf (3), in the foremost, inner corner of this bag. From this gland pro- 

 ceeds the very abundant secretion filling the space between the serrated plate and the described 

 elaborate dermal folds, as also the peculiar tube, evidently the excretory duct for this secretion. As 



M As far as I have been able to determine without dissection, this part in the specimen in hand has a length of 

 ca. 3,5 CI ", a breadth of ca. 2«n across the broad terminal part. 



2 ) Only the cartilaginous skeleton has been rendered — and scarcely quite completely — in the mentioned figure 

 liv Dumeril, as also this skeleton only is mentioned in the text (I.e. p. 682); this work, therefore, gives only a very iucom- 

 plete idea of the whole organ; the same may also be said of the short communication by Parker in Nature ; upon the 

 whole it is very difficult, without drawings and dissection, to give a tolerably clear survey of these complicated structures. 



i] Parker evidently has also seen this glandular body: In connection with the sac is a gland secreting a lubricat- 

 ing fluid, and closely resembling the well-known gland of the Elasmobranch claspers* (which gland, however, is not found 

 in all Elasmobranchii). To this is added the interesting observation: In the female, although the clasper itself is absent, a 

 small glandular sac occurs in the corresponding position;. Garmau (I.e. p. 200) has, earlier than Parker, seen the gland, 

 and given a very short and incomplete description of the pelvic appendages. He thinks that the above described cartilagi- 

 nous tube serves for conducting the secretion into the groove of the penis (i. e. the appendix-slit), when it is turned forwards, 

 and through the latter the fluid is conveyed to the oviducts of the female >. The supposed turning forward of the appendix, 



