No. 5.— Reports on the Dredging Operations off the West Coast of 
Central America to the Galapagos, to the West Coast of Mexico, 
and in the Gulf of California, in Charge of ALEXANDER AGASSIZ, 
carried on by the U.S. Fish Commission Steamer “ Albatross,” 
during 1891, Lizur. ComManpEerR Z. L. Tanner, U. S. N., 
Commanding. 
at: 
On a peculiar Type of Arenaceous Foraminifer from the American Trop- 
cal Pacific, Neustna’ Acassizi. By A. Gois. 
Amongst the vast number of remarkable forms from the deep-sea 
fauna which Mr. Alexander Agassiz brought home last year from his 
important and successful expedition in the United States Fish Com- 
mission steamer ‘“ Albatross,” in the Pacific off Central America, the 
Galapagos Islands, and in the adjacent seas,? was found this stranger 
to the Foraminifera on record. Mr. Agassiz has had the kindness to 
send me for examination a large number of specimens, together with an 
extensive collection of other foraminiferous material, dredged during 
this cruise. 
The most striking feature of Neusina is its stroma, which forms a strong 
network of bundles of very fine chitinous threads, measuring in thick- 
ness 0.003-0.006 mm., incorporated with a thin layer of finest sand and 
débris of shells. Although these inorganic constituents of the structure 
amount to about 80% of the weight of the whole after drying, the test 
preserved in spirit is to a certain degree flexible and flabby, but somewhat 
brittle, recalling somewhat the consistency of some fresh-water alge be- 
longing to the Nostoc family. It is only after drying and removing the 
sand grains and dust with a brush that the stroma comes to sight as a 
gray or yellowish flocculent felt. The meshes in the network measure in 
diameter from 0.05 to 0.08 mm. The test is leaf-formed, with outlines 
i From véew, to spin 
2 Comp. Letter and Report by Alexander Agassiz, in Bull. Mus. Comp. Zoid. 
of Harvard College, Vol. XXI. No 4 (1891), and Vol. XXIII. No. 1 (1892); and 
the Memoirs of the Mus, Comp. Zodl., Vol. XVII. No. 2 (1892), On Calamocrinus 
Diomede, Agass. 
VOL. XXIII. — NO. 3. 
