St. Andrews Marine Laboratory. 1 77 
(paleolas) of Sabellaria spinulosa and Harmothoe imbricata 
were common in the bottom-net. Tomopteris about half- 
grown occurred in mid water-, bottom-, and surface-nets. If 
there was any difference in size it was in favour of those from 
the bottom -nets. 
The Chastognaths were extremely abundant, especially in 
the midwater-net, and many were almost mature. The larger 
forms in this net measured 1J inch, and some of the same 
size were seen in the other nets. Besides the Trematode 
parasite several showed a larval Trematode in front of the 
caudal septum. 
The same forms were found in March so far as it was 
possible to examine during the intervals of storms. Many of 
the littoral Polynoidse continued fully ripe, such as Harmo- 
thoe, Evarne , and Lepidonotus. Though it is known that 
certain of the Nemerteans spawm at this time, no larval forms 
occurred in the tow-nets, in which they seem to be rarely 
found. 
Amongst the Annelids in April were also Autolytus pro- 
lifer and the epitocous form of Nereis [Iphinereis) . The 
former bred freely in the laboratory and their variations in 
colour were noteworthy. Viewed from the dorsum many 
females are pinkish with dark brown eyes. The ovigerous 
region is reddish and green, the former chiefly characterizing 
the segment-j unctions. The succeeding region is greenish in 
front, pale posteriorly. Ventrally the colours are similar but 
fainter. The alimentary canal has a dull yellowish coat. 
The coloration of the ova and embryos in the sac in some 
cases is pale, in others dull yellowish or greenish. The 
young after emergence agreed with the descriptions of pre- 
vious authors, and appeared to be more elongated than the 
larval examples of Autolytus cornutus of Alex. Agassiz * 
before the tentacles appeared. Agassiz found his forms in 
April. The reproductive period of A. prolifer in this country 
is prolonged. 
No example of Alitta virens was procured in any of the 
nets ; yet the beach in former years in March and April 
has often been strewn with splendid examples, some more 
than 3 feet in length. They would therefore not seem to be 
so characteristically pelagic at the reproductive season as 
Palolo, the Syllidians, or other Nereids. 
Tomopteris was frequent and of fair size (1 inch), while 
the Chaetognaths were on the whole less conspicuous than in 
the previous month, though some reached § inch long. A 
* “ On Alternate Generat. in Annel.,” Journ. Bost. Soc. Nat. Hist. vii. 
p. 392. 
