140 MALACOZOA. GASTEROPODA. PECTINIBRANCHIATA. 



marked with alternate dark brown and white lines, presenting 

 a tesselar appearance ; the aperture roundish, or somewhat 

 semicircular, with the margin thin, white spotted with brown, 

 the interior dark purplish-brown. Height two-twelfths of an 

 inch, breadth rather more. 



This is so nearly allied to Littorina saxatilis, from which it 

 differs only in not being so conical, in wanting the longitudi- 

 nal ridges on the turns, and in being less angulate beneath, 

 that I can hardly consider it distinct. 



It occurs abundantly on many parts of the rocky coast, from 

 Stonehaven to Peterhead, among Balani and in crevices, near 

 high-water mark. On the stones of the Pier-head at Aber- 

 deen, along with Turbo saxatilis. 



Dr. Turton, in dedicating this species to Mr. Bean, playfully 

 named it "fabalis ;" but as this would lead one to suppose the 

 shell to resemble a bean, and as Mr. Bean is not known abroad 

 by the name of Faba, I have given the specific name the usual 

 form. 



Turbo fabalis. Turt. Zool. Journ. ii. 366. PI. 12. f. 10. Turbo 

 fabalis. Flem. Brit. Anim. 298. 



7. Littorina neritoides. Flat-topped Periwinkle. 



Shell subglobose, thick, with the spire depressed and round- 

 ed, the suture distinct, the last whorl extremely large, ventri- 

 cose, longitudinally striulate, transversely striate ; the mouth 

 roundish-ovate, laterally dilated, the outer lip thinned at the 

 margin, and forming an acute angle with the last whorl ; the 

 colour olivaceous brown, dusky, greenish, yellow, orange, 

 plain, banded, or chequered ; the inside dusky, purple, pink, 

 yellow, or white. Length eight or nine-twelfths of an inch, 

 breadth six or seven. 



Very abundant on the rocky coasts, generally among fuci, 

 between the tide-marks : Stonehaven, Aberdeen, Collieston, 

 Peterhead, Gamrie, Banff, Portsoy. 



Turbo neritoides. Linn. Syst. Nat. 1232. Nerita littoralis. Linn. 

 Syst. Nat. 1258.- -Nerita littoralis. Penn. Brit. Zool. iv. 141. PI. 

 87. f. 143; Ed. n. 346. PI. 90. f. 3. Turbo retusus. Lamk. Syst. 

 vii. 48. Turbo neritoides. Lamk. Syst. vii. 48. Nerita littoralis. 

 Flem. Brit. Anim. 31 8. Littorina neritoides. Johnst. Berw. Trans, 

 iii. 269. 



GENUS 5. TURRITELLA. 



Shell turrite, with the spire very elongated and taper- 

 ing to a fine point, the whorls convex, longitudinally 



