262 
BULIvETIN of the bureau of fisheries. 
CHARACTER AND RELATIONSHIPS OF THE HAWAIIAN FAUNA. 
From the foregoing it will be seen that so far as is known the Hawaiian fauna includes 
about 25 named species of cephalopods, together with half as many more uncertain forms, 
some of which are doubtless worthy of recognition but which are only familiar to us by 
specimens either too young or too poorly preserved for a positive determination of the 
species. The total number of genera represented is 24, or about two-thirds as great as 
the total number of species. This is due to the fact that the genus Polypus with 9 forms 
listed (at least 5 of them doubtful), Argonauta with. 2 species, and Ahralia with 2 species, 
are the only genera which appear more than once in the list. (Owing to various facts 
which are to be summarized on another page, Rhyncoteuthion should obviously be excluded 
from the present discussion.) The apportionment of the fauna among higher groups 
is conveniently shown in the following table : 
Table I. 
Divisions. 
Number of 
genera rep- 
resented. 
Named 
species. 
Unnamed 
or doubt- 
ful species. 
Total 
24 
24 
One very striking feature which is brought out with particular emphasis in such a 
table is the surprising weakness of the myopsid element in the fauna. Of the four myop- 
sid genera, one is Sepioteuihis, the remaining three are Sepiolicke, and even of each of 
these but a single species has come to hand.® The total absence of any representatives 
whatsoever of the great genera Loligo and Sepia in any of the collections was entirely 
unexpected. Of course Hawaiian species of one or both of these groups not improbably 
may yet come to light, but in any case I feel that the series of specimens collected by the 
Albatross is so representative that we may assert with confidence that neither genus 
attains any very great development in these waters, or even the prominence which we 
might reasonably expect when we consider what a dominant element they compose 
in the fauna of the Malaysian Archipelago as well as of Japan. Loligo especially is so 
abundant a genus and so cosmopolitan that it would be hazardous with our present 
knowledge to deny its occurrence anywhere. In the case of Sepia, however, it should 
be remembered that with the exception of a solitary and ill-authenticated record from 
the West Indies, not a single species is known from the waters adjacent to the American 
Continent nor indeed from the entire Western Hemisphere. The group being mainly a 
littoral one, we thus have a priori grounds for suggesting that wide oceanic areas may in 
some way form a special barrier to its dispersion. If this be true we should perhaps 
expect other littoral forms, such as the Polypi, to be distributed in accordance with the 
same principle ; but this, as we shall see later, does not appear to be the case. An explana- 
tion of this anomaly may be found in the hypothesis that the dissemination of these 
other forms took place at a more ancient period. That the rise and dissemination of 
® It should be remembered, however, that to one of these species, Euprymna scolopes, belongs the distinction of being by far the 
most abimdant Hawaiian cephalopod. Nearly one-third of the total number of specimens examined are referable here. 
