. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. HYDROIDS OF WOODS HOLE. 377 spring have the distinctive elongated and spirally annulated pedi- cels and large hydrothecae. But specimens taken in summer, so far as my observations have gone, are uniformly and constantly small--only about one fourth that of typical specimens, and have extremely short pedicels, with only one or two annulae, or with none. I was not unaware that Clarke * had referred to certain variations in size, but he made no special reference to it save as an exception. It was only after careful search among
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. HYDROIDS OF WOODS HOLE. 377 spring have the distinctive elongated and spirally annulated pedi- cels and large hydrothecae. But specimens taken in summer, so far as my observations have gone, are uniformly and constantly small--only about one fourth that of typical specimens, and have extremely short pedicels, with only one or two annulae, or with none. I was not unaware that Clarke * had referred to certain variations in size, but he made no special reference to it save as an exception. It was only after careful search among colonies of typical specimens that I was able finally to find an occasional specimen of this dwarfed character. I have satisfied myself that it is but another instance of that tendency to seasonal variation which is well known in other cases. It is well, however, that it. FIG. 5. < 100. be emphasized, as well as the further fact that at certain times dwarf features are distinctive and constant. Fig. 5 shows some of these dwarfs enlarged. One other feature may be referred to in connection with this phase. Clarke called particular attention to the appearance in certain hydrothecse of this species of a "wide ring, oramented with from ten to fourteen longitudinal markings, which rises for some distance above the rim and on the summit of which there is borne either an operculum or another ring; in some cases 1 Trans. Conn. Acad. Sci., Vol. III., p. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Marine Biological Laboratory (Woods Hole, Mass. ); Marine Biological Laboratory (Woods Hole, Mass. ). Annual report 1907/08-1952; Lillie, Frank Rattray, 1870-1947; Moore, Carl Richard, 1892-; Redfield, Alfred Clarence, 1890-1983. Woods Hole, Mass. : Marine Biological Laboratory
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