494 APPENDIX. 



from the Ldbridce to the Glyphuodontidce, and it is with them 

 that we feel inclined to range Assiculus and Pseudochromis, 

 notwithstanding tlie discrepancies in the form of the intestinal 

 canal. We can, however, trace a gradation in the variation 

 of form. The normal number of caeca in the Glyphi/sodon- 

 tidce is three. In Chromis there are generally two small ones, 

 while the-BoZ^?*of the Nile, or the Chromis niloticus o{ Cavler, 

 has no pyloric csecum, but a large cul de sac to the stomach. 

 Malacanthus is widely separated from the Gl^/phisodontidce by 

 its continuous lateral line. Since these remarks were written 

 I have seen Miiller s paper, entitled, " Beitrage zur Kentniss 

 der naturlichen Familien der Fische," in which the Chro- 

 midce are indicated as a distinct family from the Glyphisodon- 

 tidce, which latter he names Labroidei stenoidei ; and Pseudo- 

 chromis, it is stated, belongs to neither of these families, because 

 it has twofold pharyngeals with a division between them. 

 Dr. Miiller promises a separate article on Pseudochromis, 

 which I have not yet seen. 



ASSICULUS PUNCTATUS. 



Radii.— Br. 6 ; D. 3 ] 23 ; A. 3 f 12 ; C. 21 ; 



P. 18: V. 1, 5. 



Plate 2./. 1, 2, 3, 4, and 5. 



This fish is as thin in the body as a lath, whence the generic 

 name. Its greatest width is at the cheek, as shewn by the section 

 yS, where the transverse diameter is about half the height* 

 Figure 4 shews the section at the gill cover, and third dorsal 

 spine, where the thickness is less ; and figure 5, represents a 

 section behind the ventrals, where the thickness is little more 

 than a tithe of the heigh , and it gradually decreases to the 

 caudal fin. The oblong profile is highest at the third dorsal 

 spine, whence it descends with a slightly convex curve to the 

 mouth, which is low down — the under jaw when extended, 



