SM1TTJA LANDSBOROVII. 341 



adopted the name Escharella, first introduced by Gray, 

 and afterwards employed in a totally different sense by 

 D'Orbigny, for a form which he made the type of a 

 family, the Escharellidte. Smitt himself has not been very 

 constant in his mode of applying the name, having first 

 given it to a somewhat heterogeneous collection of species 

 and afterwards to a mere section of it. 



It seems undesirable that terms which have been thus 

 bandied about until they have been emptied of all fixed 

 meaning should be retained ; and I have great pleasure in 

 substituting for this questionable name another which com- 

 memorates one of the most able workers in this depart- 

 ment of zoology. 



The cardinal character of this genus is the elevated 

 secondary orifice, produced and channelled in front. The 

 dentate lower margin is common to it and the following 

 genera. They also agree in having a raised peristome, 

 though in the present group it forms a perfect secondary 

 mouth ; whilst in Phylactella it only incloses the primary 

 opening in front and at the sides, and in Mucronella 

 takes the form of a mucronate process on the lower 



SMITTIA LANDSBOROVII, Johnston. 



Plate XLVIII. figs. 6-9. 



LEPRALIA LAKDSBOROVII, Johnst. B. Z. ed. 2, 310, pi. liv. fig. 9: Busk, B.M. 



Cat. ii. 66, pL Ixxxri. fig. 1, and pi. cii. fig. 1 (referred to 



L. reticvlata) : Hincks, Quart. Journ. Micr. Sc. viii. 277 ; 



DeTon Cat., Ann. N. H. tor. 3. ix. 200 (40 sep.). 

 !:-( MA HA LASDHBOROVII, Alder, Quart. Journ. Micr. So. n. B. iv. 105, pi. i?. 



figs. 1-3. 



ESCHARA FOLIACEA, var, Alder, North. Cat., Trans. Tjnes. F. 0. iii. 151. 

 LKPRALIA CRYSTALLINE, Norman, Rep. Brit. Assoc. 1866, 204. 

 ESCHAHELLA LANDOBoRovn (part.), Smitt, (Efv. K. Vet.-Ak. Porh. 1867, 



