MALACOZOA. CEPHALOPODA. FORAMINIFERA. 35 



aperture very minute, on the rounded extremity of the last turn. 

 Diameter a twelfth of an inch. 



A shell exactly similar, but with the spire reversed, or 

 turned from right to left, I have repeatedly found on Flustrse 

 from deep water. 



Very common on Flustrae, Tubularise, and other zoophytes, 

 as well as Pectens, Anomiae, Fusi, Buccina, and other shells, 

 from deep water off Aberdeen. First observed by me, in 

 September, 1842, on Tubularia indivisa. Equally common at 

 Banff, Gamrie, Fraserburgh, Peterhead, and Cruden, as shewn 

 by specimens from Mr. Alex. Murray and Miss Macgillivray. 



"Nautilus lobatulus. Turk Linn. Syst. iv. 307." — Serpula 

 lobata. Mont. Test. Brit. 515. Suppl. 160. PI. — Discorbis vesicu- 

 laris. Lamk. Syst. vii. 623. — Lobatula vulgaris. Flem. Brit. 

 Aniui. 232.— "Nautilus farctus. Fichtcl. PI. 9. f, g, b, i."— Nau- 

 tilus spiralis, lobatus, &c. Walker, Test. Min. Rar. PI. 3. f. 71. — 

 Discorbis vesicularis. Blainville, Malac. PI. 5. f. 3. 



Genus 4. Rotalia. 



Shell discoid, spiral, flattened beneath, convex above, 

 formed of a series of oblique cells ; all the whorls ap- 

 parent on the upper disk, the lower occupied by the 

 last whorl ; the partitions radiating from the centre to 

 the margin, generally imperforate ; the aperture small, 

 trigonal. 



1. Rotalia Beccarii. Beccarias Rotalia. 



Shell orbicular, depressed, spiral, lobed, convex above, flat- 

 tened beneath ; of four or five turns, which are obliquely lobate, 

 convex, with the separating lines rather deep ; the last turn 

 with about twelve lobes, and solely occupying the lower sur- 

 face, although also apparent above ; the aperture small, directed 

 rather downwards ; the colour reddish-white, but varying. 

 Diameter about half a twelfth of an inch. 



First found by me, at Aberdeen, in September, 1842, on 

 an Echinus. It occurs on various Algee and Zoophytes ; but 

 is not nearly so common with us as Discorbis lobatulus, which 

 it exceeds in regularity of form. Mr. Alexander Murray has 

 also sent it from Fraserburgh, and the Bay of Cruden. 



Nautilus Beccarii. Linn. Syst Nat. i. 1162. — Nautilus Spiralis, 

 umbilicatus Geniculis in sculptis. Walker, Test. Min. Rar. 18. 

 PI. 3. f. 63.— Nautilus Beccarii. Mont. Test. Brit. 186. PI. 18. f. 4. 

 — Rotalia Beccaria. Flem. Brit. Anim. 232. 



A shell in all respects similar, unless in being convoluted in 



