found in and about Tublpora musica* 217 



haculatus. Each has a trochoid spire of chambers, from which 

 circumferential spines are more or less projected horizontally, 

 but not all on the same plane^ as they come from the chambers 

 of the trochoid] and all possess columns of solid shell-substance ; 

 but whereas in Calcarina calcar the pores or tubulation of the 

 chambers open directly on the surface, in C. Bi^engleri they are 

 prolonged into trumpet-shaped tubes whose open extremities 

 in juxtaposition form the surface ; and these in G. hispida are 

 prolonged into points. " Hisjpida " is the designation given by 

 Mr. H. B. Brady to this variety of Calcarina (Q. Journ. Micr. 

 Sci. vol. xvi. p. 405, 1876), well represented by Dr. Carpenter 

 (Introd. pi. xiv. figs. 6 & 7) ; while in Tinoporus baculatiis the 

 pore-tubulation of the chambers of the trochoid spire is con- 

 tinued to the surface through columns of cell-like chambers 

 successively communicating with each other by pore-tubulation 

 as in all other cases of the kind. The chambers appear to be 

 alternate in adjoining columns, as in Tinojyorus vesicidaris : 

 but here the resemblance ceases ; for they are subtriangular or 

 lunate in the vertical section, and not sub-square as in T. vesi- 

 cularis ; nor have I been able to see that they communicate- 

 with each other laterally in the same way as those of. T. vesi- 

 cularis (see fig. 21, d). All these may be minor differences ; but 

 when we find that Tiiwporus baculatiis possesses in addition a 

 distinct system of interseptal canals circumscribing the cham- 

 bers of the trochoid spire and apparently opening at the ends 

 of the circumferential spines respectively, just as in Operculina 

 arabica the canals of this system open on the surface of the 

 marginal cord, it seems natural to conclude that if Tinoporus 

 bacidatus has no generic affinity with Calcarina it certainly 

 has none with Tinoporus vesicularis. 



On viewing the surfaces respectively of Calcarina calcar^ 

 C. Spengleri, and C. hispida, one cannot help being struck with 

 their resemblance to similar ones on Globigerina and Planor- 

 bulina, wherein the simple pore-opening is often prolonged 

 into a trumpet-shaped extension in the former, and a hispid or 

 pointed form in the latter. 



Dr. Carpenter evidently did not think the helix in Tinoporus 

 baculatus trochoid, or he would not have applied the term 

 " equatorial plane " to it (Introd. p. 227) ; and yet in the ex- 

 planation to plate XV., with reference to fig. 12, he states that 

 it is not distinguishable from Calcarina, using again the term 

 "median plane "=" equatorial." Now no trochoid can have 

 an equatorial or median plane ; and as fig. 2 is stated in the cxt 

 planation to represent a " section of the central portion of T, 

 baculatus passing through the median plane," it seems to be 

 a mistake ; for half the chambers still possessing their tubula- 



Ann. & Mag. N. Hist. Ser. 4. Vol. xix. 15 



