. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; Zoology. BIGELOW: COAST WATER EXPLORATION OF 1913. 313 are more branched than usual, so much so, that if they were examined by themselves they would scarcely be recognized as belonging to the species. The branching sometimes is far from being regular, the position and the length of the branches vary so much. From a stem that is otherwise normal, there may be one or two hydrothecae borne on much elongated pedicels, arising either as ordinary hydrotheca pedicels, or in the axils of these. They are annulated slightly at
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; Zoology. BIGELOW: COAST WATER EXPLORATION OF 1913. 313 are more branched than usual, so much so, that if they were examined by themselves they would scarcely be recognized as belonging to the species. The branching sometimes is far from being regular, the position and the length of the branches vary so much. From a stem that is otherwise normal, there may be one or two hydrothecae borne on much elongated pedicels, arising either as ordinary hydrotheca pedicels, or in the axils of these. They are annulated slightly at both ends as well as towards the centre, with smooth places between (Fig. 76). The stem internodes, which typically are quite uniform in length, vary much in this respect in some specimens and the nature of the geniculation at each node also varies. The terminal internode may be much prolonged into a tendril-like process such as occurs late in the season in Campanularia angulata, Obelia commissuralis, and other similar species. These tendrils are noticeable chiefly on account of their breadth and the bluntness at the end (Fig. 77). Within the. Fig. 77.— Obelia geniculata. perisarc, at the end, the coenosarc has the appearance of a developing bydranth but no case was observed where such a hydranth had really developed. In a previous paperl I referred to a specimen of this species in which he gonophores were in an unusual position. In this material a still greater variation occurs. Some gonophores are placed typically, i. e., n the axils of the hydrotheca pedicels. Others appear as those in he above reference, i. e., in place of hydrothecae (Fig. 76). Besides hese there were several in a row growing directly from the stolon Fig. 78). They have similar short, annulated pedicels to those in ne normal position and agree very well with them in other respects, 'though they are slightly larger than the others usually are. The evelopment has not been stopped at any rate, as the young
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