. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 462 DOUGLAS YINGST 30 Z 20 UJ O DC a 10 1970 1971. MAR MAY JUL SEPT APR JUN AUG OCT DEC E 2. The percentage of specimens with 13 or more segments in a given t\vo month period possessing a minimum of 4 oocytes in each of at least 3 segments. There are no data for the period of September-October, 1970. DISCUSSION Although it appears that I', longicirrata spawns during the late spring and early summer, it is doubtful that spawning is restricted to this period, as evidenced by the presence of some specimens with oocytes as early
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 462 DOUGLAS YINGST 30 Z 20 UJ O DC a 10 1970 1971. MAR MAY JUL SEPT APR JUN AUG OCT DEC E 2. The percentage of specimens with 13 or more segments in a given t\vo month period possessing a minimum of 4 oocytes in each of at least 3 segments. There are no data for the period of September-October, 1970. DISCUSSION Although it appears that I', longicirrata spawns during the late spring and early summer, it is doubtful that spawning is restricted to this period, as evidenced by the presence of some specimens with oocytes as early as March/April and as late as October (Fig. 2) and the occurrence of at least a few larvae for as much as 6 months of the year ( Fig. 1 ). Since the breeding population is chiefly composed of animals living from 100 m to 500 in and very few ovigerous specimens were found below 500 m, spawning probably occurs above 500 m. At present nothing is known about fertilization or the subsequent fate of the spawners. It is possible, however, that females could either spawn more than once or shed the eggs or embryos over an extended period of time. According to Goodrich (1945) the Phyllodocidae, which at that time included the genus Pelogobia, possess a protonephromixium which generally provides a duct through which genital products can be shed. If P. longicirrata has such nephromixia, it is unlikely that the body wall would have to be ruptured and the female sacrificed to release the ova or embryos. However they are released, these ova or embryos evidently descend from the surface because most larvae are first found between 900 m and 1200 m. It is doubtful that the larvae feed at these depths; instead, they probably live on stored yolk retained from the egg. As they mature and slowly develop the morphology necessary for feeding, the juveniles move up in the water column. This upward movement occurs during and just after the yearly phytoplankton bloom in July and early August (English, 1
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
