258 J. T. CUNNINGHAM. 



this and other errant families, becoming provided with more 

 efficient swimming organs at the breeding season by the meta- 

 morphosis of some of their parapodia, leave their burrows and 

 swim about freely in the water while they are discharging their 

 reproductive elements. I have only met with two forms of 

 the family Nereidee in sexually mature condition — Nereis 

 pelagica and Nereis virens. Specimens of the latter are 

 not unfrequently thrown up on the shore in the Firth of Forth 

 about the month of April. Solitary female specimens thus 

 cast up have occasionally been brought to me, but I have not 

 examined these very minutely. On May 1st this year we found 

 about 150 specimens among the debris at high-water mark 

 within about a quarter of a mile, close to the Granton Labora- 

 tory. Every one of these specimens proved on examination to 

 be male; they were all alive, though some had been half 

 desiccated by the warmth of the sun after the tide had left 

 them, but they were not vigorous, and from their position and 

 condition must have been dead before the tide returned. 

 These specimens were in most cases distended with milt, and 

 when handled they burst or broke into pieces on the least 

 provocation and discharged the milt copiously. I cut sections 

 of some of the nephridia of these in situ, and saw not a trace 

 of spermatozoa within the organs. If the dehiscence is normal 

 it seems most probable that the animals of both sexes die after 

 discharging their sexual products, and the dehiscence is so 

 constant that it cannot be other than a normal process. If 

 the sexual products normally escape by dehiscence, why should 

 they pass through the nephridia, or if they passed through the 

 nephridia why should dehiscence occur at all ? 



I have not seen specimens of Nereis pelagia cast up by 

 the waves upon the shore in an enfeebled condition, but we 

 found the epitokous form of the species abundantly at the 

 beginning of February ; some we found under stones between 

 tide marks, but the greater number among the roots of 

 Laminaria and under stones in the Laminarian zone. We 

 kept these often for some time in captivity, and whenever they 

 were handled, or even without being touched, they discharged 



