OF ARTS AND SCIENCES. 287 



symmetrical. The urostyle, however, is still marked by its great 

 lengtli. The permanent rays of the median fins are well advanced 

 (Plate IV. fig. 4) ; the paired fins have not changed materially since 

 the last stage (Plate IV. fig. 3). There is great diversity in the 

 coloring of the young of Lumpus. In the youngest stages (Plate IV. 

 figs. 1-3) the head, in a line drawn nearly vertically below the base 

 of the anterior dorsal, is of a light chocolate brown, with a darker 

 brown band extending from the nostrils above the eye to the base of 

 the anterior dorsal. A light blue band extends from the rear of the 

 eye to the top of the operculum, and in front of the eye to the nos- 

 trils. A blue spot of similar tint is found at the posterior base of the 

 dorsal and at the base of the caudal extremity of the posterior dorsal. 

 The rest of the body is straw colored. The young of stage repre- 

 sented in Plate IV. fig. 4, were usually of a bright olive green, 

 darkest towards the dorsal side, with the same blue band extending 

 towards the operculum from the rear of the oi'bit, with one or two 

 round blue spots above the level of the pectorals along the lateral 

 line. Other specimens were of a bluish neutral slate tint, uniformly 

 spotted with darker pigment cells, with the same blue band between 

 the eyes, above the nostrils, and behind the eyes. This was also the 

 coloring of the oldest of the young specimens caught (Plate V, figs. 

 1, 3), resembling in general the bluish coloring of the adult, only of a 

 darker tint. 



The intermediate stages varied greatly in coloring ; some were of 

 a yellowish brown spotted with chocolate-colored patches, with light 

 greenish bands behind the eyes, and five roundish spots of the same 

 color along the lateral line, and a similar number of larger spots along 

 the base of tlie posterior dorsal, extending, in some specimens, along 

 the median dorsal line of the body to the colored band extending 

 between the eyes. Other stages, with a similar arrangement of ellip- 

 tical spots of a bluish tint along the dorsal and lateral lines, were of a 

 reddish brown color with pigment patches of a darker greenish or of 

 a brownish color, the abdominal region being of a lighter color. 



In the stage of Plate V. figs. 1, 2, the anterior part of the body 

 already assumes somewhat the angular outline characteristic of the 

 adult, though these young stages are all more elongated than the 

 adult, having also the head comparatively well separated from the pos- 

 terior part of the body. The young in the stages of Plate V. figs. 

 1, 2, do not as yet show any traces of the prominent rows of spiny 

 tubercles formed in the adult. These were developed to a slight 



V 



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