'6. HKNIOCHUS 41 



spines are anchylosed together: the mterhsemals of the first two 

 anal spines form one bone only, with a broad triangular process an- 

 teriorly ; the bone itself is very long, its length being equal to that 

 of the first twelve vertebrae together. 



2. Heniochus monoceros. 



Cuv. dr Val. vii. p. 100. pi. 176 ; Bleek. Verh. Batav. Genootsch. xxiii. 

 aiatod. p. 21. 



D. i|. A. ^. L. lat. 58. L. transv. 9/24. 



The fourth dorsal spine exceedingly elongate, filiform. A conical 

 protuberance above each orbit, another on the nape of the neck. A 

 black band from the first two dorsal spines, occupying all the neck, 

 the eye, the forehead and the snout ; a second band from the fifth, 

 sixth and seventh dorsal spines to the belly, including the root of 

 the pectorals and the ventrals, which are of a' deep black ; a third 

 band from the pbstevior dorsal si^ines, descending obliquely back- 

 wards and occupying the posterior half of the anal fin ; the anterior 

 half is black-edged. 



Sea of the Mauritius. 



o. Large specimen. Mauritius. From^the Collection of the Zoolo- 

 gical Society. 



3. Heniochus chrysostoma. 



? Heniochus chrysostomus, {Parkins,^ Cuv. ^ Val. vii. p. 99 ; Cuv. 



Hegne Anim. III. Poiss. pi. 40. f. 2. 

 Heniochus chrysostomus, (Solander^ Voy. Beech. ZooJ. p. 62. pi. 18. f. 1. 

 melanistion, Bleeker, Banda, lii. p. 98. 



D. -^. A. ^. L. lat. 45. L. transv. 7/25. 



The fourth dorsal spine exceedingly elongate, filiform, with a 

 broad floating membrane reaching to its top. A very slight pro- 

 tuberance above the orbit, none on the neck. A black band from 

 the origin of the spinous dorsal to the belly, occupying the whole 

 operculum, the upper portion of the prseoiierculum, the eye, the root 

 of the pectorals, and the ventrals, which latter are entirely black ; a 

 second band from the thii'd to the sixth dorsal sjjines, descending 

 obhquely backwards and occupying more than the posterior half of 

 the anal ; a third broad band along the base of the soft dorsal, ex- 

 tending to the back of the tail and the root of the caudal fin. 



East Indian Archipelago. (Otaheite ?) 



a, h. Fine specimens. Amboyna. Purchased of Mr. Frank. 



4. Heniochus varius. 



Ruysch, Pise. Amb. tab. 20. f. Q; Romrd, i. 30. 164; Valent. iii. 



p. 369. f. 71. 

 Taurichthys varius, Cuv. Sf Val. vii. p. 148. pi. 181 ; Cuv. Regne Anim. 



lU. Poiss. pi. 41. f. 2 ; Bleek. Verh. Bat. Grn. xxiii. Chcetod. p. 25. 



D. ii. A. ^. L. lat. 53. 

 The fourth dorsal spine elongate. A protuberance above each 



