1'*^ PISCES. 



Some of these Chsetodons, properly so styled, are distinguished 

 from the others by a filament formed by the prolongation of one, or 

 several of the soft rays of the dorsal. ( 1) 



Finally, some are remarkable for the very small number of the 

 spine of their dorsals. (2) 



Chelmon, Cuv. 



Separated from Chaetodon on account of the extraordinary form 

 of the snout, which is long and slender, only open at the extremity, 

 and formed by a most excessive prolongation of the intermaxillary 

 and lower jaw. Their teeth are very fine and crowded, (en Jin ve- 

 lours) rather than like hairs. 



One species, Chset. rostratus, L., Bl., 202, has the faculty of 

 spurting drops of water on the insects it perceives on the shore, 

 and thus bringing them within reach. It is a common pastime 

 of the Chinese at Java.(3) 



Heniochus, Cuv. 

 Differs from the true Ch^etodon, because the first spines of the 

 back, and particularly the third or fourth, rapidly increase in length, 

 forming a filament sometimes double the length of the body, and re- 

 sembling a kind of whip. (4) 



Ephippus, Cuv. 



Distinguished by a dorsal deeply emarginated between its spinous 

 and soft portions^ the spinous part, which has no scales, can be 

 folded mto a groove formed by the scales of the back. 



In one of the subdivisions, there are three spines in the anal fin 

 and oval pectorals. ' 



America produces a species (Uph. gigas, Cuv., remarkable 

 for the great enlargement of the first interspinal of its dorsal 



5;-Ch. Umaculatus, Bl., 219, l,~Ch. plebeius, Gm.,~Ck. unimaculatus, B] , 

 201, 1;Ch. sehanus, Cuv., Seb., Ill, xxv, 11; Ch.ocellatus, El, 211, 2 



(1) Chset. setifer, Bl., 426, U-Ch. auriga, Tovsk.;-Ch. principalis] Cuv., Ren 

 part II, Ivi, 239, Valent., No. 407. 



(2) These species are new, as well as many others which belong- to precedinff 

 subdivisions they will be described in our Icthyology. 



(3) Schlosser, Trans. Phil., 1767, p. 39.-Add: Ch. longirostris, Brousson, Dec 

 Icthyol. 



(4) Chwtodon maa-olepidotus,-L., BL, 200," 1; the Chxt. amminatus, L., Mus. 

 Ad. Fred., XXXIII, f. 2, appears to be a mere individual variety of it; the 

 Chset. comutus, L., Bl., 200, 2, of which the Ch^t. caneseem, L., Seb., Ill, xxv, 7, 

 IS only a young uncoloured specimen. 



