176 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 97 
are distributed in museums ‘‘as widely scattered as were the original 
habitats.”’ I have tried to make this review as complete as possible 
so that students interested primarily in biological oceanography and 
invertebrates in general can use it without recourse to scattered papers. 
Drawings have been made of all the species examined, usually from 
unmounted material, with the aid of a camera lucida. Thus the ele- 
ment of perspective must be taken into consideration when studying 
the drawings, and extreme examples of foreshortening are indicated 
whenever they occur. The measurements of the larger specimens 
were made with a pair of dividers; for the smaller specimens the fol- 
lowing system was used: A series of millimeter scales, enlarged with 
the camera lucida by various lens combinations, was prepared, and 
the object to be measured was projected by the lucida against the 
appropriate scale. Of the 70 species discussed in this paper, 9 are 
described as new (3 of these have been indicated by preliminary 
diagnoses in an earlier paper, 1943b), and 2 referred to their genus. 
No attempt has been made to include complete synonymies of well- 
known. species, but all important local references, insofar as I have 
been able to find them, have been included. 
Unless otherwise indicated, the material listed is in the United 
States National Museum. Material from other museums is referred 
to by the following abbreviations: the Museum of Comparative 
Zoology at Harvard, M. C. Z.; the Peabody Museum of Natural 
History at Yale, Y. P. M.; the American Museum of Natural History, 
New York City, A.M.N.H. This system has not been used for the 
Albatross collections, individual lots of which are about evenly divided 
between the National Museum and the Peabody Museum. The 
number of specimens listed from each Albatross station has been com- 
piled from the collections now in these two museums and does not 
represent the original collection in many instances, since no complete 
records have been kept of specimens sent to European museums from 
time to time. The more complete set, including specimens of all the 
species mentioned, is in the National Museum. 
The taxonomy of the larger genera (e. g., Nymphon, Colossendeis, 
Achelia, Anoplodactylus) is in a sad state of disrepair, but revision of 
their species must await that unrealized millennium when existing 
types and scattered collections are available to one specialist for 
redescription and comparison. Collections from European and 
Arctic regions have been accumulating for more than a hundred 
years, and the inadequate descriptions of earlier workers have resulted 
in an almost hopeless tangle, which academic taxonomists have done 
little to unravel. 
The most outstanding recent taxonomic papers on the Pycnogonida 
are Gordon’s Discovery Report (1932), with its fine review of the 
