OF NEW SOUTH WALES. 327 



specimens of H. Phillipi, as is shown in figs. 16 and 17 (pi. 24). 

 The posterior teeth of H. Francisi were all of almost the same 

 size, and shewed a distinct mesial line on their upper surface. 

 The mesial line of some teeth was nodose. 



In the upper jaw I found 25 vertical rows of teeth ; in the 

 lower jaw, 23. As regards the number of teeth in the vertical 

 rows, I could not attain to any certainty, as the mouth could not 

 be opened far enough to enable me to count them with precision.* 



ON THE EXTERNAL GENITAL ORGANS OP THE MALE 



H. PHIIiLIPL 



As I have before me a large number of sketches of these parts, 

 as seen in various species of sharks, in which, in spite of a simi- 

 larity in many poiuts, there are yet considerable variations, it 

 appears to me expedient to postpone giving a comparative resume 

 of these drawings until in proper order, a selection of the sketches 

 in question has been given. 



In the mean time I may observe that the drawings Figs. 

 20 — 24, pi. 24 — are the more deserving of attention, that 

 they were made from fresh preparations, the parts being care- 

 fully preserved in situ during the preparation of the transverse 

 and longitudinal sections.** 



REMARKS ON THE ILLUSTRATIONS. 



Since a faithful figure, in addition to the considerable saving 

 of time (as well to the author as to the reader), which it is the 

 means of effecting, has the advantage over a lengthy description 

 of being demonstrable to the eye, and gives the reader a better 

 idea of the object. I have, as already observed (page 319), re- 

 garded the illustrations as of primary importance. In order to 

 obtain, as far as possible, correct outlines, which is the most 

 important point, I have had recourse to photography, and to a 



* Figures of tlie anterior-teeth of H. Quoyi are to be found botli in tlie Magasin 

 de Zoologie, 1839, and also in Dumeril. (Atlas, pi. 3, figs. 16 and 17.) 



** A description— on the whole correct— of the external sexual parts of the male 

 Plagiostomata {organes copulateurs or ap2)endices externes or membres accessoires), is to 

 be found in A. Dumeril. (Histoire Nat. des Poissons. Tome I., 1865, pag 233 et seq.) 

 A short dissertation on the significance of these organs as ^' or ganes destines a une veri- 

 table intromission," is to be found in the same work. (Pag 240, et seq.) 



