224 



RADULA OF THE TAENIOGLOSSA 



CHAP. 



seen in Ovula^ Pedicularia, and the Cyclostomatidae. Here the 

 outermost of the two marginals is by far the larger and broader, 

 and is strongly pectinated on its upper edge ; in the Oyclostoma- 



FiG. 127. —Two rows of the 

 radula of Cypraea tigris L. 

 X30. 



tidae the pectinations are rather superficial ; in Ovula (where 

 both marginals are pectinated) they are decidedly deeper ; in 

 Pedicularia they are deeper still, and make long slits in the 

 tooth, tending to subdivide it altogether. In Turritella the 

 number of marginals is said to vary from none (in T. acicula) to 

 three (^T. triplicata)^ but the fact wants confirmation. Solarium 

 is an aberrant form, possessing simply a number of long uncini, 

 which recall those of Conus ov Pleurotoma^ and is therefore hard 

 to classify ; the allied Torinia has a radula which appears allied 

 to Ovula or Pedicularia. In Triforis the teeth are identical 

 throughout, very small, about 27 in a row, tricuspid on a square 

 base, cusps short. 



The normal formula of the Taenioglossa is 2.1.1.1.2 ; in 

 Lamellaria^ 1.1.1 ; in Triforis^ 13.1.13, or thereabouts. 



(f?) Ptenoglossa. — This 

 section consists of two 

 families only, which cer- 

 tainly appear remarkably 

 dissimilar in general habits 

 and appearance, viz., the 

 lanthinidae and Scalarii- 

 dae. In all probability 

 their approximation is 

 only provisional. The 



Fig. 128. -Portion of the radula of Jan^/iina f^dula, which in lantllina 

 conuniims Lam. x 40. i - ci 



is very large, and in iSca- 

 laria very small, possesses an indefinite number of long hooked 



