268 DR, H. HICKS ON" THE MORTE SLATES, AND [May 1 896, 



found in the same quarry are such as would he expected to occur 

 with it in beds of Lower Wenlock age. 



Pound in the Mullacott and Shelfin quarries, near Ilfracombe. 



Rhvnchonella Lewisii(?), Davidson. (PI. XI. figs. 1-4.) 



Many specimens of this species have been found in the rocks on 

 the side of the path leading down to Barricane Beach, but, like 

 most of the fossils found in the Morte Slates, usually in a greatly 

 distorted condition. The specimens have also for the most part lost 

 the ornamentation characteristic of this species, but traces of it 

 are sometimes left in some of them. The pinched appearance of 

 the mesial fold is still retained, and the number of ribs in the 

 mesial fold and sides agrees exactly with those in the Shropshire 

 specimens from beds of Wenlock age. On p. 180, op. cit., Davidson 

 says that ' the range of this species is said to be in the Llandovery 

 and Wenlock rocks ; I am, however, acquainted with the shell only 

 from the last-named formation, in which at some localities it is 

 exceedingly abundant.' Hitherto the only locality in the Morte 

 Slates in which it has been found by us is at Barricane in Morte 

 Bay, in association with Spirifera Hamlingii, Lingula mortensis, etc. 

 Mr. Bather was kind enough to compare our specimens with those 

 in the "Natural History Museum, and said that they agreed more 

 closely with the typical specimens of Eh. Lewisii in the National 

 Collections than with any other species. 



Rhynchonella Stricexandi (?), Sowerby. (PI. XI. fig. 11.) 



A few imperfect specimens of this species have been found in the 

 Mullacott quarry. In size and shape the shell agrees with those 

 which occur in the Wenlock Limestone and Shale in other areas. 

 It has a very convex form, is from 12 to 15 lines in length, and the 

 surface is ornamented with from 25 to 30 narrow, simple, angular 

 ribs. 



Spirifera Hamlingii, sp. nov. (PI. XL figs. 5 & 6.) 



The specimens are compressed and distorted, but they show that 

 the shell was wider than long and moderately convex. The hinge- 

 line is nearly straight, rather longer than the width of the shell, and 

 somewhat pointed at the cardinal angles. Dorsal valve convex, 

 with a well-raised, wide, mesial fold. Surface of valves ornamented 

 with about 36 moderately strong rounded ribs, of which nearly a 

 third occur on the mesial fold. They are frequently crossed by fine 

 concentric lines, and here and there the larger ribs appear to be 

 ornamented with fine lines more or less parallel with them. Area 

 narrow. 



Pound at Barricane, in Morte Bay. 



Orthts rustica, Sowerby. (PI. XI. figs. 7-10.) 



This species occurs in fair abundance in the Mullacott quarry, and a 

 few specimens have also been obtained from the rocks on the northern 

 side of Barricane Beach. In each place they are much distorted, 

 but they show the characteristic ornamentation mentioned by 

 Davidson. He says at p. 239 (Monogr. Pal. Soc. ' Brit. Sil. Brach/) 



