98 



BULLETIN 71, UNITED STATES NATIONAL MUSEUM. 



TROCHAMMINOIDES PROTEUS (Karrer). 



Trochammina, pro£ras Karrer, Sitzb.kais. Akad.Wiss. Wien,vol.52 (Abth. 1), 1865 

 (1866), p. 494, pi., fig. 8 (not 1-7).— H. B. Brady, Rep. Voy. Challenger, Zool- 

 ogy, vol.9, 1884, p. 341, pi. 40, figs. 1-3. — Haeusler, Neues Jahrb., Beil., vol. 

 4, 1885, p. 28, pi. 3, fig. 24(25-27?).— Egger, Abh. kon. bay. Akad. Wiss. Mun- 

 chen, vol. 18, 1893, p. 266, pi. 5, figs. 7, 8 [?].— Eimer and Fickert, Zeitschr. 

 wiss. Zool., vol. 65, 1899, p. 694, fig. 42 (in text).— Flint, Rep. U. S. Nat. 

 Mus., 1897 (1899), p. 281, pi. 25, fig. 3.— Bagg, Proc. U. S. Nat. Mus., vol. 34, 

 1908, p. 128. 



Ammodiscus proteus Rhumbler, Arch. Protistk., vol. 3, 1903, p. 281, fig. 131 (in 

 text). 



Description. — Test of several coils, usually planospiral, each coil 

 usually constricted to form several chambers, but the early coils 

 sometimes unconstricted, wall composed of fine sand and a yellowish- 

 brown or reddish-brown cement, fairly smooth, chambers variable 

 in length, aperture large, with thickened lips. 



■ ' wt r «" 



Figs. 142-144.— Trochamminoides proteus. x 25 (after Brady). 



144 



Diameter 1-1.5 mm. 



Distribution. — There are but two records for this species in the 

 North Pacific, one Challenger station 224 in 1 ,850 fathoms, west of the 

 Caroline Islands, and the other Albatross station H4566, at a depth 

 of 572 fathoms, near the Hawaiian Islands, recorded by Bagg. 



This species in its typical form is clearly divided into chambers of 

 uniform size, especially in the last-formed coils, but the earlier coils 

 may be undivided or irregularly constricted. Its development indi- 

 cates the derivation of the many-chambered planospiral forms from 

 a type like Ammodiscus. 



The eight figures given by Karrer show various forms of tests, 

 planospiral or involute, undivided tests belonging to Ammodiscus or 

 Gordiammina and other trochoid divided tests like true Trochammina 

 and in fig. 8 a test similar in form to the recent specimens placed 

 under this specific name. Brady a has already noted the various 

 forms grouped by Karrer under this species and has proposed the 

 restriction of the name given by Karrer to the form represented by 

 fig. 8 of Karrer. This seems reasonable, and I have adopted the 

 same restriction. 



Haeusler's figures also show various forms under this specific 

 name. The specimen shown in fig. 24 may belong here, but the others 

 are hardly this species as here restricted. 



a Rep. Voy. Challenger, Zoology, vol. 9, 1884, p. 341. 



