REPORT ON THE PYCNOGONIDA. 147 
ledge of the species of Pycnogonida known to occur on the coasts of New England and 
Nova Scotia. With two exceptions (Achelia scabra, Wilson, and Nymphon macrum, 
Wilson) the species here described are the same as those of a former paper by Mr Wilson, 
published in the Trans. Connect. Acad. Sci., vol. v. pp. 1-26, 1880. The new Achehia 
is quite unknown to me, but MVymphon macrum, Wils., is undoubtedly the species 
which I have described in my report (p. 45) as Nymphon brevicollum. The Challenger 
specimens were taken south of Halifax (83 fathoms), those described by Mr Wilson 
in the Gulf of Maine (85 to 115 fathoms). 
The other paper (Reports on the Results of Dredging, under the Supervision of 
Alexander Agassiz, along the East Coast of the United States, during the summer of 1880, 
by the United States’ Coast Survey Steamer “ Blake,” Commander J. R. Bartlett, U.S.N., 
commanding. xiii. Report on the Pyenogonida, by Edmund B. Wilson; Bulletin of 
the Museum of Comparative Zodlogy at Harvard College, vol. viii., No. 12, Cambridge, 
Mass., March 1881, pp. 239-256, pls. i—v.) contains descriptions of ten species of Pyeno- 
gonids, five of which are new. These belong to three genera, two of which are con- 
sidered by the author as new. The new species are in the first place two species of 
Colossendeis, Jarzynsky, Colossendeis colossea, and Colussendeis macerrima. Then a 
new genus Scaeorhynchus, with the species Scweorhynchus armatus, is proposed ; finally, 
the new genus Pallenopsis, with the species Pallenopsis forficifer and Pallenopsis 
longurostris, is described. The descriptions are illustrated by very good figures. On 
comparing these figures and descriptions with those of my report, there can be little 
doubt that Colossendeis colossea and C. macerrima are very nearly related to, if not 
identical with, my Colossendeis gigas and C. leptorhynchus. As to the genus Scaeo- 
rhynchus, 1 do not think there are sufficient grounds for separating it from Ascorhynchus, 
G. O. Sars. Neither the presence of dactyli on the first pair of legs, nor the structure 
of the rudimentary mandibles (antennae) makes it proper to separate these genera: 
Scacorhynchus (like Gnamptorhynchus, Bohm) is only a synonym of Ascorhynchus. 
The species armatus, Wilson, seems to be different from those hitherto described, and 
also from those of the present report. 
The new genus Pallenopsis is intended to embrace those species which come near to 
Phoxichilidium, but which are characterised by ten-jointed accessory legs present in both 
sexes, and by three-jointed mandibles. Three (perhaps four) species described in my 
report show these characters also, and (pp. 82 and 88) I have been long in doubt whether 
I should not propose a new genus for these species. I did not take the step because I do 
not wish to augment the number of genera more than necessary until our knowledge 
of generical characters is more perfect. Mr Wilson is not so slow in proposing new 
genera ; in the present instance, I believe, however, that his proposal has a fair chance of 
being accepted. The two species described by Mr Wilson are, I believe, different from 
those described in my report. 
