HYDROIDS OF THE HAWAIIAN ISLANDS COLLECTED BY THE STEAMER 
ALBATROSS IN 1902. 
By C. C. NUTTING, 
Professor of Zoology , State University of Iowa. 
Previous to the Hawaiian cruise - of the Albatross almost nothing was known 
regarding the hy droid fauna of that region. So far as the writer has been able to 
ascertain, but three species had been reported from those waters — two having been 
collected by the Challenger and one having been mentioned by Hartlaub as collected 
by Professor Schauinsland from near the island of Laysan. 
The collection forming the basis of this report is thus from practically virgin 
territory, and when it is remembered that the Hawaiian Islands are farther removed 
from any continental mass than any other group of similar size, it will be seen that 
forms of unusual interest would probably be found which would throw light on the 
morphological and geographical relationships of the Hydroida as a whole. With 
these considerations in view it will be readily understood that the study of this 
collection was undertaken with keen interest. The result, however, has been far 
beyond an}' reasonable anticipation. It is doubtful whether any other collection, 
approximately of the same size, made during the last quarter of a century has 
yielded so great a number of unusually interesting forms. 
Of the d9 species collected 29 are new, and as a whole these latter are more 
certainly distinct from previously known forms than is usually the case. As might 
have been expected, the majority of the novelties were found among the Calyptero- 
blastea, but the most surprising occurred among the Gymnoblastea, a suborder that 
has comparatively few representatives in tropical waters. Of the 7 species of these 
latter, 2 were well-known Holarctic forms, 2 were new species of a genus hitherto 
known only from the Mediterranean, and 2 were so different from anything hereto- 
fore known that the writer has been unable to place them in any previously defined 
family, and has been forced to establish new families of Hydroida for their reception. 
Another interesting and unexpected feature of this collection is the unusual 
proportion of forms provided with fascicled stems, more than half of the entire 
number of species being - thus characterized, and all but one of the gvmnoblastic 
forms. As has elsewhere been shown®, the accessory tubes of the fascicled stem are 
in reality modified hydrocladia, and their utility lies in giving additional strength to 
the stems. Why this particular feature is so often developed in the Hawaiian region 
it is hard to imagine, especially as by far the greater number of species were taken 
in depths presumably beyond the influence of pronounced wave action. 
Nutting, American Hydroids, Part II, p. 5, 1304. 
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