THE GOBY FAMILY. 173 



the adult length being, according to Day, about 2| inchew, 

 while the authors of the Scandinavian Fishes state that it 

 is from 60 to Go mm. ; they also give a very complete account 

 of the coloration of this species. 



Nilsson's Goby. {Crystallogohius Nilssonii, Dub. and Kor.) 



The free eggs of this species have not yet been described, 

 though they are visible enough in the body of the ripe female, 

 in spirit. 



The post-larval stages are met with in July. Thus on the 

 20th July a specimen 7 mm. in length ' presented a head with a 

 large pair of eyes and a prominent mandible below the open 

 mouth. From the somewhat truncated condition of the 

 premaxillary region, however, the mandible, when closed, is 

 probably bent obliquely upward, and it is also truncated, the 

 margin indeed in each being nearly straight, with a prominence 

 at the outer end, from which one or two sharp teeth project 

 beyond the mucous membrane. The truncated margin is 

 shorter in the premaxillary region, and after an interval there 

 is another prominence with a smaller tooth. From what 

 appears to correspond to the lower margin of the preopercular 

 region, two prominent spines project outward and backward. 

 The branchiae have simple papillae. The body tapers gently 

 from the head to the tail, the notochord passing nearly straight 

 out in the latter, though a considerable thickening (hypural) 

 exists beneath. The dorsal marginal fin begins behind the 

 head and joins the caudal. Ventrally it extends from the vent 

 to the caudal. The latter shows only embryonic rays and these 

 are less distinctly marked throughout the marginal fin — 

 dorsally and ventrally. The pectorals are rather large and 

 long, with true rays, the upper and lower being short, the 

 median much longer. They are deeply tinted with black 

 pigment on the inner surface, or what probably is more or less 

 ventral when in motion. It is chiefly developed in the inter- 

 radial integument in the form of isolated squares or patches. 



1 W. C. M. Ninth Rep. ,<?. F. B. 1891, p. 322. 



