34 Messrs. W. K. Parker and T. It. Jones on the 



hemispherical knobs of this exogenous shell-matter quincuncially 

 arranged over the whole surface, three or four cells being in- 

 cluded in the area of each quincunx. This style of exogenous 

 growth is also recognizable in some of the spherical lobeless 

 individuals. 



The bead-ornament suggests the name O. sphcerulata for this 

 variety*. 



9. A still larger variety of the massive Orbitolina, having a 

 sugar-loaf form, a flat or slightly concave base, and a diameter of 

 £ inch, occurs -fossil at Ciply (Belgium), in the uppermost 

 Cretaceous series. It is much mineralized, but appears to have 

 the same structure as the foregoing, including the crystalline 

 knobs on the angles of the septa ; but these clear beads are 

 connected together by strings of granules of the same substance, 

 small and variable in size, protruding on the edges of the septa. 

 As a variety, this may be named O. spharulolineata. 



10. In the same deposit are somewhat smaller and globular 

 specimens, in which the granular growth of the septal edges is 

 still greater ; so that continuous, rough, sinuous walls of division 

 are produced, marking out irregular polygonal spaces, including 

 one or more cells, the faces of which lie low down below the 

 surface. Essentially similar septal projections constitute the 

 limbate feature in Rotalia Beccarii, var. Schrceteriana, and R. 

 repanda, var. Carocolla. Similar globular Orbitolina (O. globu- 

 laris, Phillips, sp.) are common in other Cretaceous deposits. 



Milleporal globularis, Phillips (Geol. Yorks. pi. 1. f. 12) and 

 Woodward (Geol. Norf. pi. 4. f. 10-12), Tragos globularis, Reuss 

 (Bohm. Kreid. p. 78, pi. 20. f. 5), Coscinopora globularis, D'Orb. 

 (Prodrom. ii. p. 284) and Morris (Cat. B. Foss. 2nd edit. p. 27), 

 is our Orbitolina globularis 'f. Michelin's Ceripora Avellana (Icon. 

 Zooph. p. 208, pi. 52. f. 13), from Sarthe, appears to us to be 

 a large specimen of the same variety. Its probably adherent 

 habit and perforated condition are not inimical to this view. 



* Denys de Montfort (Conch. Syst. i. p. 146) has given a curious hybrid 

 picture of his Triophorus baculatus, which consists of a three-spined Orbi- 

 tolina, according to its surface-ornament and its vertical section, but out- 

 lined apparently after a three-spined Calcarina Spengleri, fig. e, pi. 15, in 

 Fichtel and Moll's ' Test. Microsc' The indication of an aperture (the 

 broken newest chamber in Calcarina) is also after F. & M. Its sectional 

 aspects appear to have been taken, the vertical (Orbitoline) from nature, 

 the horizontal (Calcarine) from Fichtel and Moll's fig. k, with the sectional 

 feature of the spine (also Calcarine) added from some other source. Some 

 stellate form of O. spharulata may perhaps claim the name of O. bacu- 

 lata, Montf. 



t The characteristic structure is visible in some specimens preserved in 

 the British Museum, and formerly in the collection of the late John 

 Brown, Esq., of Stanway. 



