46G ANNUAL HECORD OF SCIENCE AND INDUSTRY. 



pendent one ; the subdivisions can only be determined when 

 more material has been accumulated. 



"Animal" Fishes. 



There is a family of fishes the Gobiids very rich in spe- 

 cies, most of which live near the bottom, and many of which 

 are eminently adapted for such stations, for their ventrals 

 are modified in an infundibuliform manner for adhesion to 

 rocks, etc. There are, however, a few representatives of the 

 family whose compressed body and lateral eyes proclaim 

 them to be free swimmers in mid water. Among; the most 

 interesting of these are a couple of fishes inhabiting the Eu- 

 ropean seas. They are the Boreogobius pellucidus and Crys- 

 tallogobius JVilssonii. These have been especially investi- 

 gated lately by Professor Robert Collett, of Christiania, Nor- 

 way (see Proceedings of the Zoological Society, London, 1878, 

 pp. 318-339). Both species are quite abundant at certain 

 seasons in the Christiania Fjord, but while the latter has only 

 been found in the Norwegian and Swedish waters, the for- 

 mer extends round the European coast-line to the Adriatic 

 and Black seas. 



As just noted, they are much compressed, their eyes are 

 lateral, and, moreover, when living, they are quite transpar- 

 ent, so much so that their presence in the water is chiefly 

 manifested by their dark-colored eyes. The Boreogobius has 

 some large readily-deciduous scales, but the Crystcdlogobius 

 is entirely naked. They not only swim freely in the water, 

 but associate together in large numbers. The Boreogobius 

 is by far the most abundant, and occurs in enormous num- 

 bers; it is caught in nets drawn at depths of from one to fif- 

 teen fathoms. The Crystcdlogobius appears to be less common 

 and to dwell at greater depths. Both spawn, in the North, 

 chiefly about the end of June and the early part of July. As 

 the spawning season approaches, and in its height, the males 

 develop large canine teeth, and become otherwise differenti- 

 ated. After the spawning season the adults suddenly disap- 

 pear, and where hosts were a short time before, none can be 

 found except the young. It is, therefore, supposed by Pro- 

 fessor Collett that the adults die after spawning, and that 

 the species are, in fact, "annual vertebrates," performing the 

 entire cycle of their life-history in a year, and succeeded 



