134 BULLETIN OF THE BUREAU OF FISHERIES 
would probably follow a southwest wind, and in this case the species might be 
S. serrodentata, although deep-water collections off the coast in warm weather often 
reveal large numbers of S. elegans. Such a condition may have taken place in August 
1903 (see fig. 35). On August 4, 1922, one specimen of 8. serrodentata was taken 
and another on August 5. 
In the 16 years that S. elegans has been recorded, with one or possibly two excep- 
tions, none appeared before November or remained after July. The usual time of 
appearance is December. In 1899 a few were taken on December 23, and in 1898 
many suddenly appeared on December 12. In 1922 two specimens were found on 
October 4, one on October 5, two on October 10, and gradually increased from then 
until early December, when large numbers appeared. The highest point is usually 
reached in February. During this month they swarm. 
It is interesting to compare these results with those of Dr. H. B. Bigelow (1914) 
in Massachusetts Bay. In late December he found S. elegansin the tow. Through- 
e 
a 4 
s ‘oO 
Rive Biacifinwpitiod Mies co Bines 
Ne 
Fig. 34.—Occurrence of Sagza evegans in surface collections from June, 1922, to December, 1923. 
, distribution in 1922; —.—, distribution in 1923 
out January and February the numbers increased until they formed the bulk of the 
plankton. Occasionally 8. serrodentata was taken, but always S. elegans was by far 
the most abundant. When the water began to grow warmer in early March, the 
numbers fell off rapidly, so that on March 4 only 12 specimens were taken. The 
last Sagittee appeared on April 14. This is merely additional evidence of the 
similarity of plankton north and south of Cape Cod in winter. 
In March and April, 1923, swarms of S. elegans with ripe eggs were abundantin 
Great Harbor. During the latter part of April large numbers of eggs appeared and, 
together with the eggs of the mollusk Littorina litorea, made up the greater part of 
the tow. On May 2 the first young were observed. These increased rapidly in 
number and were very abundant throughout May and June. The last specimen was 
