422 The Rev. R. T. Lowe on the Fishes of Madeira, 

 Fam. Squalid^e. 



Carcharius falcipinnis. " Faqueita." C. corpore supra griseo- 

 cinereo, subabbreviatOf medio crassiore s. altiore^ utrinque atte- 

 nuato : rostro brevi, lato, depresso^ apice obtuso : oculis rotun- 

 datis : pinna dor sail prima alta, triangularis subantica s. supra 

 medium pinnarum pectoralium posita : pinnis j^ectoralibus fal- 

 catis, angusiis, elongatisy apice obtusis : pinna dorsali secunda 

 analique oppositis : ventralibusque parvis, Rariss. 

 An Squalus ustus, Dum.? 



It is perhaps only for want of better materials for comparison that 

 I have been unable to refer this Shark precisely to the above-indi- 

 cated or to some other described species. It is about three feet long, 

 and the female differs in nothing from the male. The teeth are 

 precisely similar to those of the " Tintureira" (C. glaucus, Cuv.). 



The ** Marraxo" proves to be, as I suspected, Lamna cornubica, 

 Cuv., adult, or of large size. 



Gen. Acanthidium. 



Corpus gracile, elongatum. Spiracula magna. Pinna dor sales 

 duse, antice spiniferse ; secunda majore postica, caudse approximata. 

 Pinna analis nulla. Pinnce ventrales, subposticse s. secunda dorsalis 

 subanteriores. 



Denies utriusque maxillae dispares, parvi : superioris laniarii, plano- 

 triangulares, tenues, acuminati ; acumine recto ; basi utrinque den- 

 ticulo aucto ; antice triseriati, lateribus biseriati : inferioris incisorii, 

 acumine utrinque a medio oblique deflexo, uni- vel bi-seriati. Cauda 

 oblique oblonga, apice truncata. 



This new genus appears exactly intermediate between the esta- 

 blished genera of Cuvier, Spinax and Centrina : agreeing with the 

 former in its elongated form, and with the latter in the teeth. 



The ventral fins are placed more backward than in Spinax, but rather 

 forwarder than in Centrina, i. e. neither halfway between the two 

 dorsal fins, nor opposite the second dorsal fiu, but just before the 

 second dorsal fin, which begins exactly opposite the termination of 

 their base. The tail or caudal fin resembles that of Spinax, rather 

 than of Centrina, and the spines of both the dorsal fins are reflexed 

 as in Spinax, forming the fore-edge of each fin. The pectoral fins 

 are abruptly truncate. The second dorsal fin is greatly larger than 

 the first; in which it differs equally from Spinax and Cetitrina. 

 The teeth are not arranged quincuncially, but behind each other in 

 rows. 



Two species have occurred, both of which have hitherto been con- 

 founded with Centrina. 



