South- African Land- M oil usca. \M 



wliicli, on being opened to view, did not sliow inside the 

 folded walls as in Kerkophorus {nunctus, M. & P.^ but 

 the sac contained a good deal of extraneous loose matter, 

 which under a high power had all the appearance of being 

 the broken-down walls ot" the vestibule, the result of 

 decomposition, the specimen not being in the best state of 

 preservation. 



'I'he male organ has a short flagellum, a ca:!cum, and an 

 accessory gland near the retractor muscle, which is long. 

 The s[)ermatheca is a globose sac on a thick stalk-like duct. 



In a row of the rudula the teeth are arranged as follows : — 



5G . 1 . 10 . 1 . 10 . 1 . 56 = 67 . 1 . 67. 



The central and admedian as in aloicola, ]\I. & P., var., and 

 other Cape species. The transition tooth similar, but on a 

 narrower basal plate ; it is succeeded by some three teeth, the 

 outer cusp of which is below tlie terminal point, all the 

 succeeding laterals being unevenly bicuspid and diminishing 

 gradually to the margin, where they become very minaie. 



Pelfatus phi/tosti/Iiis, Bs. 

 Ann. & Mag. Nat. Hist. ser. 3, vol. xiii. p. 492 (1864). 

 Original localiiy. Colesberg. 



Peltatus arnotti, Bs. 

 Ann. & Mag. Nat. Hist. ser. 3, vol. .\iii. p. 491 (1864). 

 Original locality. Colesberg. 



The animals of these last two species have not yet been 

 seen by me. 



EXPLANATION OF THE PLATES. 

 Plate I. 



Kerkophorus conieus ?, PIV. Maritzburg. 



Fiff. 1. Animal, viewed from the right side. X 1"5. 

 Fig. 1 a. Ditto, left side. X I'o. 



Fuj. 1 b. The visceral sac, showing left shell-lobs, the region of the 

 branchial sac, kidney, &c. X 4'o. 



Microkerkus symmetricus, Craven. Pretoria. 



Fig. 2. Animal, viewed from the right side. X l-'j. 

 Fig. 2 a. Ditto, left side, x lo. 



Plate 1L 



Peltatus caledonensis, sp. n. Cape Colony. 



Fig. 1. Animal, anterior part viewed from the left side, to show the 



