THE BLENNY FAMILY. 217 



mentioned represent further stages of the season's growth. On 

 22nd July, S.E. of the Isle of May in 30 fathoms an example 

 of 40 mm. occurred. 



In August they reach 45 mm., most of the adult characters 

 being present except the pigment. Some captured between tide- 

 marks at Lochmaddy were, however, only 31 mm. In Guernsey, 

 again, one of 116 mm. in July is probably 15 months old. 



From what has been said above, the gunnel will be seen to 

 belong to those shore-loving fishes with a demersal egg, the young 

 of which instead of being brought up beside its parents, passes 

 through an early migration which involves a pelagic sojourn 

 in the offshore water, before eventually assuming its normal 

 habits in the littoral region (cf. Herring, Sand-eels). 



THE VIVIPAROUS BLENNY. (Euckelyopus (Zoarces) 



viviparus, L.) 



This very interesting form has long been studied by natural- 

 ists since Dr Schoenevelde of Hamburg in 1624 brought it 

 under notice, and Forchhammer of Kiel (1819), H. Rathke (1824) 

 and F. Stuhlmann of Kiel (1887) have since more particularly 

 dealt with the subject, the dissertation of the latter, which is 

 illustrated by excellent figures, being especially noteworthy. One 

 of us in 1885 1 also made some remarks on the ovarian young, in 

 which Willughby's opinion of a winter breeding-season was 

 corroborated, and the habits of the young, referred to below, 

 were observed, while Mr Holt, who also studied it at St Andrews, 

 followed with additional observations. 



The viviparous blenny has a single roe or ovary lying along 

 the middle line of the body, and in its walls the eggs are 

 produced in the usual manner, but instead of being ripened 

 and shed externally they are developed in cavities or follicles 

 situated on processes or papilla?, fertilized in the ovary and 

 then hatched, the young, moreover, being retained in the 

 spacious ovarian chamber till they have attained a consider- 

 able size. They are then discharged externally to shift for 

 themselves. 



1 W. G. M., Ann. Nat. Hixt. June 1885, p. 430, Plate xvi. tigs. 1 aud '2. 



