FORAMINIFEEA OF THE NORTH PACIFIC OCEAN. 87 



their distinctive characters broken down as claimed by Brady, but 

 seem to be well characterized. In their earlier stages they may not 

 be easily distinguished, but this is also true of various allied forms in 

 many groups. 



PENEROPLIS PERTUSUS (Forskal), var. PLANATUS (Flchtel and Moll). 

 Plate 37, fig. 3. 



Nautilus (Lituus) arietinus (part) Batsch, Conch. Seesandes, 1791, p. 4, pi. 6, 



figs. 15a, b. 

 Nautilus planatus, var. B. Fichtel and Moll, Test. Mior., 1803, p. 91, pi. 16, 



figs. Id, e, f. 

 Peneroplis planatus d'Orbigny, Ann. Sci. Nat., vol. 7, 1826, p. 285, No. 1; 



Modeles, No. 16.— II. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, 



p. 204, pi. 13, fig. 15. 



Description. — Test in the young close coiled, becoming in the adult 

 broad and complanate, the chambers increasing rapidly in height, 

 wall ornamented with numerous longitudinal costae, broken at the 

 depressed sutures; aperture consisting of a long, single row of small 

 circular pores along the median line of the flattened apertural face. 



Distribution. — Bagg records this variety from Albatross station 

 4694 in 865 fathoms off the Hawaiian Islands. I have specimens 

 from a single Nero station in the same region 2039 in 24 fathoms. It 

 also occurred in the material from Gaspar Straits, from Hongkong, 

 and from the Tuscarora from Manila Bay. 



In some respects the young of this variety may resemble the typi- 

 cal form, but the height of the chambers increases fairly early and 

 it is- much flatter as well. The apertural characters of the adult are 

 also seen fairly early in the development. 



PENEROPLIS PERTUSUS (Forskal), var. CARINATUS d'Orbigny 



Plate 37, fig. 4. 



Peneroplis carinatus d'Orbigny, Foram Amer. Merid., 1839, p. 33, pi. 3, figs. 7, 

 8— H. B. Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, p. 205, pi. 13, 

 fig. 14. 



Description. — Test planospiral, nautiloid, each coil completely cov- 

 ering the preceding to the umbilicus, test close coiled throughout, 

 sutures usually strongly limbate; wall smooth; aperture consisting of 

 numerous small circular pores scattered over the roughly triangular 

 apertural face. 



Distribution. — Specimens of this variety were found in some 

 numbers in the material from Gaspar Straits but were not found 

 elsewhere in the North Pacific material. 



This form seems very different from most of the others and seems 

 more worthy of specific rank than the others included here. 



