rOEAMINIFEEA OF THE PHILIPPIIsrE AND ADJACENT SEAS. 351 



side partially hidden by the supplementary skeleton which is more or 

 less developed in all the species; aperture typically a row of small 

 openings along the inner margin of the apertural face; canal system 

 well-developed. 



This genus is represented by several recent species, which are con- 

 fined to the shallow water of the tropics and the Mediterranean. 

 In the Philippine material four species are found, some of them rep- 

 resented by abundant specimens. 



A study of the thi'ee genera — Calcarina, Baculogypsina, and Sidero- 

 lites — as well as Tinoporus Montfort, has shown very definite rela- 

 tionships. In an earlier short paper I discussed these genera. It 

 Seems that the genus Tinoporus Montfort is too mdefinite to be of 

 value, the species haculatus Montfort being now probably recognizable, 

 but as he refers in his generic description to certain characters which 

 belong more closely to what must be, by the study of the characters, 

 now called Baculogypsina spTiaerulata, the whole genus should be 

 eliminated. 



The type species of Calcarina is Nautilvs spengleri Gmelin. This 

 species is definitely taken as the genotype by d'Orbigny. This is a 

 well-defined species, as will be shown. Of the other species, C. 

 defrancii, described by d'Orbigny, is recognizable, and also C. hispida, 

 described by H. B. Brady, The fourth species here called C. haculatus 

 Montfort makes up the series. 



Of the other genera, Siderolites Lamarck, of which the type is S. 

 calcitrapoides Lamarck from the chalk of Maestricht, seems to have a 

 very definite place. Material from the type locality was studied and 

 shows that the species is much more complex than most of the species 

 of Calcarina, and should be used in a definite way for S. tetraedra 

 Giimbel, which occurs in the Philippine collections. 



Baculogypsina, erected by Sacco in 1893 on account of the uncer- 

 tainty of the identity of Montfort's Tinoporus, is here used for 

 Baculogypsina sphaerulata (Parker and Jones), which is the species 

 of the Challenger report and other works usually passing as Tinoporus 

 Montfort. 



Calcarina has the smiplest development of the three and is least 

 specialized, apparently going back geologically to the Cretaceous. 

 The following species occur: 



CALCARINA SPENGLERI (Gmelin). 



Plate 75, fig. 1. 



Nautilus spengleri Linnaeus, Syst. Nat., ed. 13 (Gmelin's), 1788, p. 3371, No. 10. 



Calcarina spengUri d'Orbigny, Ann. Sci. Nat., vol. 7, 1826, p. 276, No. 4. — H. B. 

 Brady, Rep. Voy. Challenger, Zoology, vol. 9, 1884, p. 712, pi. 108, figs. 5, 7.— 

 CusHMAN, U. S. Nat. Mus., pt. 5, 1915, p. 72, pi. 31, fig. 2. 



Description. — Test lenticular, biconvex, chambers numerous, in a 

 close-coiled trochoid spire of three or four volutions, each with several 

 chambers, but the sutures not usually all distinguishable on the dorsal 

 side except the last few; wall covered by a supplementary skeleton, 

 the surface with raised tubercles of solid, translucent material, espe- 



