GENERA AND SPECIES. 123 



Idalia. (GONIODORID&.) Plate xxxiii. 

 611. elegans, ij in. white, spotted with rose; gills 18. 



leachii, i in. white, centre of back with filaments ; 



gills ii. 



aspersa, J in. reddish or yellowish, spotted with orange and 



brown ; gills 10. 



inaqualis, f in. grey, speckled with yellow and brown ; mouth 



with 4 filaments in front ; gills 9. 



pulchella, f in. pale blue, centre of back without filaments ; 



gills IT. 



quadricornis f in. mottled brown and white mantle, with 2 



filaments in front ; gills 8 or 9. 



Isocardia. (CYPRINIDM.) Plate v. 



54. cor, 3|X3f in - she11 globose, yellowish white, periostracum 



brown, 



Jeffreysia. (JEFFREYSIID^.) Plate xxiv. 



435. diaphana, ^ in. whorls 4^. 



436. opalina, -$ in. whorls 3^, shell oval and semi-transparent. 

 437- globularis, -$ in. whorls 3^, shell globular and transparent. 



Kellia. (ERYCINID&.) Plate vii. 



73. suborbicularis, \ in. x \ in. right valve with two lateral teeth. 



74. cycladia, ^in. x-^in right valve with two lateral teeth and a 



cardinal. 



Lachesis. (MURICIDsE.) Plate xxvi. 



510. minima, in. shell ridged and cross-ribbed, apex twisted 



on one side. 



Lacuna. (LITTORINIDM.) Plate xxiii. 



Suture excavated 



394. tenella, in. whorls 5. 



392. crassior in. whorls 6 or 7. 



Suture not excavated 



395. puteolus, in. whorls 3 or 4, umbilicus narrow. 



396. pallidula, % in. whorls 3 or 4, umbilicus very wide. 



393. divaricata, J in. whorls 6. 



Of the three varieties of 393, quadrifasciata. is keeled ; 395 has five varieties of no im- 

 portance ; and 396 has three named varieties, of which the most noticeable is patula, 

 which has a flat spire. , 



Lamellaria. (LAMELLARIID&.} Plate xxiii. 



377. perspicua, $ in. shell ear-shaped, first whorl twisted. 



