Mr. J. Miers on the Menispermacese. 187 



acquainted. The head has a sudden elevation over the eyes, 

 towards the neck, afterwards becoming broader. The external 

 lamellse of the gill-cover are very finely radiated ; the lamellae on 

 the summit of the head above the eyes are thin and radiated 

 from the centre in a similar manner. Ossicles of gill- membrane 

 four or five in number, very thin. This membrane joins to the 

 lower jaw, and almost attains the tip of the mandible; hence 

 the jaws, on account of the magnitude of the prey, can be dilated 

 to a great extent ; and this is also much facilitated by the very 

 singular structure of the mandible, which is composed of small 

 broad bones like the branchiostegal rays of other fish. 



Postbranchial fins very long, sharply pointed. The dorsal fin 

 extends beyond two-thirds of the length of the fish ; the second 

 dorsal takes its rise nine inches from the extremity of the tail, 

 and is cutaneous in texture, as it usually is in Salmon, but very 

 thin and without ossicles. The two ventrals are at the distance 

 of 224 inches from the snout, being 2\ inches long and 5 inches 

 before the adipose fin ; another simple fin commences on the 

 belly, probably behind the anus ; for there does not appear to be 

 a vestige of the anal. Caudal fin 3 inches long, broad, with the 

 posterior margin apparently forming the segment of a circle. 

 No further characters are distinguishable, on account of the 

 dried state of the specimen. 



XXXIII. — On the Menispermacese. 

 By John Miers, F.R.S., F.L.S., &c. 



[Continued from p. 95.] 



42. Chondodendron. 



This genus, proposed in 1 794 by the authors of the ' Flora 

 Peruviana' (Prodr. 132) has been recognized by few botanists. 

 De CandoUe (Syst. i. 522) referred the typical plant to Cocculus, 

 while Persoon regarded it as a species of Epibaterium (Ench. ii. 

 561). Original specimens exist in the herbaria of the British 

 Museum and of M. de Boissier, each with a label in Ruiz's 

 handwriting ; so that the identification of the genus is placed 

 beyond doubt : this is a fact of some importance, because hitherto 

 its real characters have been involved in much obscurity. Poppig 

 in 1838 described and figured a plant (also from Peru) under 

 the name of Chondodendron convolvulaceum, which he conceived 

 to be a second species with female flowers : but in this reference 

 he was greatly mistaken ; for it belong^ to my genus Odonto- 

 carya ; and this mistake has given rise to the many misconcep- 

 tions that have been entertained concerning the genus. When 



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