144 BULLETIN OF THE BUREAU OF FISHERIES 
Members of the family Harpacticide sometimes appeared during the winter 
months. Only one species (Tachidws brevicornis) had a definite free-swimming 
period. Egg-bearing females were taken in towings throughout the spring, often 
in great abundance. This, apparently, was the only one of the group that had a 
pelagic period during the year. Others may have been free-swimming but did not 
occur in sufficiently large numbers to indicate it. 
4 gq. & Bini non onl Comantiahede 
a 
Se 
ves. 
Ne 
Fic. 45.—Occurrence of Pseudocalanus elongatus in surface collections from June, 1922, to December, 1923. 
«-.---, distribution of adults in 1922; —_— —, distribution of immature specimens in 1922; ————, dis 
tribution of adults in 1923; —. —, distribution of immature specimens in 1923 
The winter forms collected during the past year were as follows: 
Pseudocalanus elongatus. Acartia clausii. 
Calanus finmarchicus. A. longiremus. 
Centropages hematus. A. bifilosa. 
Temora longicornis Tortanus discaudata. 
Eurytemora herdmani. Microsetella norvegica. 
E. hirundoides. Idya furcata. 
Metridia lucens. Tachidius brevicornis. 
Over 50 species of parasitic copepods have been recorded from Woods Hole. 
Often they are taken in surface collections, but they do not home form a part 
of the plankton except in their larval stages. None appeared in 1922. In 1923 a 
male Caligus schistonyx was taken. 
Three lists of free-swimming copepods have been made for this region. Wheeler 
recorded 30 species, but most of these were taken in the vicinity of the Gulf Stream 
and are extralimital. Sharpe recorded 60 species in 1911, of which only 23 occurred 
at Woods Hole. Twelve others were quoted from Williams’ s report on Narragan- 
sett Bay, and the remainder were taken from Wheeler’s list. Summer, in 1911, 
compiled 25 (plus 12) species from the combined data of Wheeler and Sharpe, no 
new additions being made. 
