1904 - 5 .] The Pelagic Fauna of the Firth of Clyde. 787 
The early stages in the autumn were far more numerous than 
those in the spring, and occasionally occurred in shoals. 
The Free-swimming Larval Stages of Polych^tes. 
In 1902, larval stages were found in the tow-net from January 
till the beginning of May, and again from the end of October to 
the end of December. They were usually scarce, and never 
became even fairly common. Not many different kinds were 
seen, and most of them were not identified. 
Magelona papillicornis, F. Muller. 
The larval stage was seen on the following dates : — 
In 1901, eleven specimens were taken between 18th and 
22nd July. 
In 1902, one specimen taken on 30th July. 
Mitraria. 
Korschelt and Heider, 1895, i. p. 276, fig. 124. 
Watson, 1901, p. 254, pi. xxv. fig. 17. 
In 1901, a specimen was taken in Millport Bay on 22nd July. 
This is the free-swimming larval stage of Owenia fusiformis. 
CELFTOGN ATH A. 
Sagitta bipunctata, Quoy et Gaimard. 
In 1901, Sagitta was very scarce from May till October. On 
8th May two specimens were taken, and no more were seen until 
30th September. It was found throughout October, but was 
always scarce. 
In 1902, Sagitta was taken throughout the year in every month 
from January to December. 
Up to the end of February only large adults (20-28 mm. in 
length) were seen. These, after breeding, began to die off during 
March and April, and had completely disappeared by May. 
