156 



ZOOLOGY OF THE VOYAGE OF THE BEAGLE. 



spines that follow short, and not protruding much beyond the skin. First spine in the dorsal 

 very strong, aculeated at the anterior edge, but not at the sides ; no third spine in this fin. 

 Second dorsal and anal even. Caudal rounded. 



D. 2— 24; A. 21; C. 12; P. 13. 



Length 2 inc. 3 lin. 

 Colour.— Not noticed in the recent state. The ground colour has probably been altered by the 

 spirit, but the markings are still very distinct, and accord tolerably with Bloch's figure, except 

 that the obli'que bands on the posterior part of the body, in front of and above the anal, are 

 darker ; while they alternate with four white ones, which are particularly conspicuous. Pos- 

 sibly these white bands may have been originally blue, as the narrow stripes descending from 

 the eyes to the pectorals, which evidently were of that colour, are nearly faded to a white. 

 There is also a white stain on each side of the tail, where the spines are, which appears to 

 have been blue originally : the spines themselves are deep shining black. 



This specimen shows the black transverse bands between the eyes, and the broad band 

 passing from the eye to the pectoral, between the narrow blue ones above alluded to, all repre- 

 sented by Bloch, but not observed by Mr. Bennett in the specimen figured in the " Zoology of 

 Beechey's Voyage." 



Habitat, Tahiti. 



The above specimen was taken by Mr. Darwin at Tahiti. It is quite small, 

 and differs in some respects from the figures of Bloch and other authors, but it 

 is evidently referable to the B. aculeatus. The species is probably subject to 

 variation in respect of colouring. 



1. Aleuteres maculosus. Richards. 



Aleuteres maculosus, Richards, in Proceed, of Zool. Soc. 1840. p. 28. 



Form.— Oval, somewhat approaching to fusiform behind, very much compressed. The greatest 

 depth one-third of the entire length. Skin covered with little granular points, terminating in 

 very minute bristles, and communicating a slight roughness to the touch, when the finger is 

 passed from tail to head. Snout rather prominent and acute : jaws equal. Dorsal spine 

 springing from above the middle of the orbit of the eye ; strong, with four rows of sharp 

 prickles at the four angles, pointing downwards, and very regularly set : second dorsal spine 

 very minute. The second dorsal and anal fins have been lost in this specimen, and their form 

 and number of rays cannot be determined. The pectorals are small, each with twelve rays. 

 Caudal rounded, also with twelve rays. 



Length 5 inc. 4 lines. 

 Colour. — " Mottled with pale blackish green, leaving white spots." — D. — In its present state, the 

 skin is nearly gone from long maceration in impure spirit : such portions as are left accord 

 well with Dr. Richardson's description, appearing of a mouse-grey, with darker mottlings. 

 There are three or four rather indistinct dark ascias across the caudal. 



