862 



SYSTEMATIC HISTOET OF THE INFTISORIA. 



p. 107, pi. 7. f. 12-15 ; Wallich, TMS. ^iii. 

 p. 48, pi. 2. f. 18 ; West, TMS. viii. p. 152, 

 pi. 7. f. 13. St. George's Bank, Atlantic 

 Ocean, (vi. 25.) " This species was 

 found in considerable numbers in the 

 contents of the stomach of the Botryo- 

 dactijla f/mndis.'' Awns 30 to 50 times 

 longer than the body. 



C. Peruviamim (Bri.). — Valves hemi- 

 spherical, with two very stout, long, 

 recurved, spinous awns proceeding from 

 the centre of the rounded ends. Br JMS. 

 iv. p. 107, f. 16-18. In Peruvian guano. 

 A remarkable and very distinct species, 

 characterized by the rounded apex of 

 the valve. Lateral view circular ? 



3 * Frustules laterally oval or circular ; 

 awns smooth. 



C. Tetrachcsta (E.). —Frustules with 

 four, very long, filiform, smooth awns on 

 each side. KSA. p. 138. Antarctic Sea. 

 Diam. without the awns, 1-1152". 



0. DichcBta (E.). — Frustules with two, 

 very long, filiform, smooth, often flexu- 

 ose^ awns on each side. KSA. p. 138. 

 Antarctic Sea. Diam. without the awns, 

 1-1152" to 1-720". The description is 

 too imperfect to enable us to distin- 

 guish the species from some of the fol- 

 lowing ones. 



C. confervoides (n. sp.). — Frustides 

 large, quadrate ; awns stout, smooth, 

 arising a little beneath the rounded 

 angles; lateral view circular. Mount's 

 Bay (stomach of Ascidise), Cornwall. 

 We have seen only one concatenated 

 specimen; it formed a short, very fra- 

 gile, conferva-like filament of about 12 

 joints, which were equal in length and 

 loreadth and in close apposition. Internal 

 colouring matter brownish, and collapsed 

 into a roundish spot in the centre of 

 each frustule. 



C. Wighamii (Bri.). — " Frustules cup- 

 shaped, with a band round the mouth of 

 the cup, and a neck or bulb proceeding 

 from the centre ; beset with minute short 

 spines or papillae in all parts except the 

 band; lateral view oval; awns elon- 

 gated, smooth." Br MJ. iv. p. 108, pi. 7. 

 f. 19-36. In brackish water, near Brey- 

 don, Great Yarmouth. " Boiled in acid, 

 the filaments break up, and the frustules 

 in an isolated state, and detached rings 

 with the horns proceeding from them, 

 are all that can be detected. The rings 

 may readily be distinguished from the 

 frustules seen endwise, as they are open 

 and without dots, wnile the frustules 

 seen endwise are dotted" (Bri.). We 



have seen no perfect specimen of this 

 interesting species ; but as Mr. Bright- 

 well's fig. 12 shows two joints similar 

 to other species of this genus, we are 

 inclined to regard the Goniothecia-like 

 bodies as internal cells, of the same 

 nature as the internal cells of Himan- 

 tidium, Meridion, &c., which we believe 

 to be sporangia ; but whatever their 

 true character may be, we have scarcely 

 a doubt that Mr. Brightwell is right in 

 supposing Goniothecimn crenatnm, G. his- 

 pidum, G. Navicida, and G. barbatum to 

 be allied forms belonging to the same 

 genus as this species, (^t:. 24.) 



C. ineurvum (Bail.). — Frustules in 

 front view linear, with smooth, filiform, 

 recm'ved awns arising from the angles ; 

 lateral view oval. Bii. /. c. pi. 7. f. 9-11. 

 Fossil. Virginia, Peru\dan guano. In 

 stomach of Ascidise, Penzance. Easily 

 known by its small size and slender 

 recurved awns. 



C furcillatum (Bail.). — Awns of ad- 

 joining frustules closely approximate 

 below, then diverging and becoming 

 nearly parallel ; lateral ^dew oval. Bai. 

 on Microsc. Forms in the Sea of Kamt- 

 schatka, p. 3, pi. 1. f. 4. Common in the 

 Sea of Kamtschatka. The minutest spe- 

 cies in the genus. 



C. didymus (E.). — Frustules longer 

 than broad, gibbous or angular on the 

 outer margin, and usually slightly so on 

 the inner margin also; awns smooth, 

 filiform, arising from the angles. Bri. 

 /. c. pi. 7. f. 3-7; KSA. p. 138; EM. t. 35 a. 

 18. f. 4. Common in Peruvian guano. 

 Stomach of Ascidise, Penzance. A va- 

 riable species, distinguished by its angu- 

 lar or gibbous margins ; lateral view 

 oval. Ehrenberg's two figures in the 

 'Microgeologie' difier from each other, 

 as well as from any specimens we have 

 seen. Greatest diameter 1-1080". 



C. Gastridmm (E., Bri.). — Frustules 

 binate, smooth, transversely oblong, 

 truncated at each end, abruptly dilated 

 at the middle of the ventral surface, not 

 contiguous, Bri. /. c. pi. 7. f. 8. = Goyiio- 

 thecium Gastridium, EM. pi. 18. f. 91. 

 Virginian guano. Ehrenberg describes 

 and figures it with an external umbo 

 (gibbous), thus approaching to C. didy- 

 mus. 



C. armatum (\Vest). — Frustules qua- 

 drangular, forming a compressed fila- 

 ment ; angles excavated ; from each an^le 

 arises a long, obtuse, cui-ved seta, with 

 several acute ones at the base. West, 

 TMS. viii. p. 151, pi. 7. f. 12. Abundant 

 on various parts of the coast of England. 



