SEA-FISHERIES LABORATORY. 289 
gatherings a sudden and remarkable change was noticed 
in the plankton. Diatoms were much less frequent than 
in the gatherings taken a few days before—and also 
than in those taken a couple of days later. But the 
notable feature of both hauls was the large catch of 
young Schizopods, which turned out on examination to 
be Nyctiphanes norvegica, decidedly a rare crustacean 
in our sea, though common in deep water on the West 
coast of Scotland. There were about 900 specimens of 
these young Nyctiphanes in the coarse net, and 160 in 
the fine. The swarm must have been a large one, and 
a very unusual occurrence inside Port Erin Bay in the 
surface waters. 


3 7 3 “ 5 5 z 
: : : 2. 1 
Se ee ee a ee 
‘a b> Seed Sb ca yp P > ° 
cee ss Pema ahd boas ae 
= cae N Mi = OE: te sy s) Fy 
1910. 
January... 3 0 14 227 183 =1,109 ~—:1,669 49 0 
February 3 0 7 2,078 461 628 431 19 5 
IM src trcacx 6 381 ) 5,531 1,362 462 4,375 39 =: 102 
April aeons Cae el 745 31 = 7,280 447 840 3,220 1,955 109 
MAY esas: 91 62 117 318 250 400 375 4,538 30 
JUNG ... 020 14 186 295 5,241 0 566 644 6,050 19 
July seers 26 144 466 298 68 873 2,212 4,014 6 
August... 17 170 195 242 11 1,219 1,040 3,216 6 
September 177 167 29 494 523 334 1,884 5,522 1 
October ... 196 47 150 348 226 1,485 1,150 3,087 0 
November 3 0 20 250 312 1,430 1,174 273 0 
December 7 9 23 174 403 662 1,079 211 0 

Of these, Sagitta and Orkopleura have been discussed 
above. The Medusae belong to many different species 
and even families, and several distinct curves probably 
overlap. The set that are abundant in May are probably 
quite distinct from those found in late autumn. 
The Echinoderm larvae and the Polychaet larvae 
are most abundant in April, but here again different 
sets appear in succession during summer and autumn. 
