No. 11. — Reports on the Scientific Results of the Expedition 

 to the Eastern Tropical Pacific, in charge of Alexander 

 Agassiz, b^ the U. S. Fish Commission Steamer ^' Albatross,^' 

 from October, 1904, to March, 1905, Lieut. Commander L. M. 

 Garrett, U. S. N., Commanding. 



XIX. 



Pycnogonida. By Leon J. Cole. 



During the cruise of the "Albatross" in the Eastern Pacific in 1904, 

 pycnogonids were taken at four stations. In all there were only six 

 specimens obtained, three of which, however, belong to a species previ- 

 ously undescribed. When it is recalled that the " Albatross " made 

 explorations in this same region in 1891, it is not surprising that the 

 other two species represented by the remaining three specimens should 

 have been taken in the collections made at that time. A few additional 

 notes on these two species, together with a description of the new form, 

 are presented herewith. 



Ascorhynchus agassizii ScHiMKtwiTscH. 



PI. 1, fig. 1 : PI. 3, figs. 5, 6. 

 Biill. Mus. Comp. Zool., 1893, 25, p. .36, pi. 1, figs. 4-6 ; pi. 2, figs. 12, 13, 16, 17. 



One female ; Station 4-630; Nov. 3, 1904; lat. 6° 52' N. ; long. 81° 42.5' W. 

 (Gulf of Panama) ; 556 fatlioms ; bottom, green sand, large globules. 



One female; Station 4631 ; Nov. 3, 1904; lat. 6° 26' N. ; long. 81° 49' W. 

 (GuU^of Panama) ; 774 fathoms : bottom, green sand. 



These two specimens were taken at stations not far apart, and but a compara- 

 tively short distance from the locality where the species was first found, in 1891. 

 They are of about the same size, and agree very closely with the description 

 given by Sclinnkewitsch. His description is, however, apparently based entirely, 

 or nearly so, upon the male, and his figures are from a specimen of that sex. The 

 females taken in 1904 are noticeably smaller than his measurements ;^ the dorsal 



^ The specimen from Station 4631, which is slightly the larger, measures 32 mm. 

 from tip of proboscis to tip of caudal segment, when straightened out, while the 

 extent along the third legs is about 13.5 mm. 



