101 



prominent, spread at the suture, and raised into a small sharp 

 tooth. Great Britain. 



72. Sc. Greenlandica. (pi. xxxiv. fol. 105 and 110.) 

 " Clathrus Greenlandicus," Chemn. 11. p. 155. f. 18/8-79. 

 planicostata ? Kiener; subulata, Couthoy ? Boston Journ. Sc. 

 Vol. 2, No. 1. 



T. elongata, crassa, spiraliter sulcata; anfractibus con- 

 tiguis, vix prominentibus ; varicibus decumbentibus ; ine- 

 qualibus, ad suturam expansis, reflexis, et ad anfractum prox- 

 imam elevatis ; apertura sub-triangulari, colore, inter varices, 

 griseo fulvescente. 



T. juniori, varicibus expansis, reflexis. 



Like Sc. Turtonis in general form, but with fewer whorls : 

 the varices more elevated and spread, and the whorls spirally 

 grooved. From Greenland and Newfoundland. 



73. Sc. line ata. (pi. xxxiii. f. 49, 50, 51.) Say. 



T. pyramiclali, sub-ventricosa, imperforate, leevi'; anfrac- 

 tibus rotundatis, rapide crescentibus; ultimo magno, linea 

 spirali, elevata, ad inferiorem partem anfractuum varicibus 

 plerumque tenuis ; nonnullis magnis, simplicibus, numerosis : 

 apertura magna ; colore inter varices, fusco nigricante, ali- 

 quando fasciis binis ; vel pallide fulva, fascia rubra. 



The elevated line at the lower part of the whorls, is very 

 slight in this species, but easily perceptible, the varices are 

 irregular, some of them large. From America. 



74. Sc. clathrus. (pi. xxxv. f. 131, 132, 134.) Linneus, 

 Sc. lamellosa, Lam. var. Sc. monocycla. Kiener. 



T. pyramidali, ventricosa, leevi, linea elevata spirali ad in- 

 feriorem partem aufractuum ; varicibus 11, distantibus, lami- 

 natis, extantibus, ad suturam sub-expansis, ad apicem oblique 

 continuis ; apertura magna, ovali ; colore, inter varices fulvo 

 vel fusco-maculato, prope suturam fascia lata ; vel griseo, fascia 

 nigra. 



This well-known species to which the name of lamellosa is 

 generally applied, is ascertained, with tolerable certainty, to 

 be the true clathrus of Linneus, having the basal keel which 

 is without the common British species bearing that name. 



Mediterranean and West Indies. 



75. Sc. coronata. (pi. xxxv. f. 133.) Lamarck. 



T. lamellosae simillima, sed varicibus magis numerosis : 

 colore albo, inter varices seriebus tribus macularum fuscarum. 

 The varices are much more numerous than in the last, and 



