40 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I28 



phores, and chaetognaths, there are undoubtedly several generations 

 a year, although the same individuals probably do not reproduce more 

 than once. In all three of these groups both larval forms and adults, 

 with all intermediate stages, were often present at one time. 



Both budding and sexually mature hydromedusae were found 

 throughout the summer months. Plankton tows during winter were 

 not extensive enough for obtaining information on the development 

 and reproduction of these forms during that season. 



The jellyfish Chrysaora sp. contained eggs and swimming larvae 

 on November 19, 1949. The commonest sea anemone (Stomphia 

 coccinea) of the region was filled with large eggs on October 14, 1949. 

 Would these develop into swimming larvae during the winter or would 

 they be retained within the sea anemone until spring before becoming 

 swimming larvae ? 



A large percentage of the bryozoans collected during February con- 

 tained eggs. It is probable that these eggs were produced from food 

 stored during summer and that the larvae would be released at the 

 beginning of the open season. 



The development of one species of polychaete worm was followed 

 sufBciently to give information on how long the eggs are carried in- 

 side the body. The syllid Autolytus jallax Malmgren was found with 

 large eggs inside the body on October 11, 1949. On January 25, 1950, 

 a few specimens were found carrying egg sacs in which there were 

 developing embryos, and on March 29, 1950, and April 7, 1950, there 

 were hundreds of these worms swimming around with their egg sacs. 

 The egg sacs from individual worms contained eggs and embryos in 

 varying stages of development. Thus from the time large eggs were 

 seen within the bodies of Autolytus jallax to the time when the ma- 

 jority of these worms were carrying sacs containing eggs, or de- 

 veloping embryos, a period of 5 to 6 months had elapsed. 



Data on related forms are given in table 4. 



Female stolons of the related Autolytus prismaticus were found on 

 August 6 and 30, 1948, with eggs massed inside their bodies. A female 

 stolon of Autolytus alexandri with swimming setae and with the body 

 filled with eggs was dredged on February 18, 1950. Females of Cir- 

 ratulus cirratus with eggs inside their bodies were found from the 

 first week in August until the first week in September. A male of 

 the sabellarid Idanthyrsus armatus Kinberg spawned August 9, 1949. 

 The terebellid Terehellides stroemi M. Sars had ripe eggs and sperm 

 on September 26, 1949, and Potamilla neglecta M. Sars was found in- 

 cubating eggs on September 6, 1949. The terebellid Thelepus cin- 

 cinnatus (Fabr.) had ripe eggs and sperm on October 11, 1949. 



