532 Prof. C. Lapuorth — On Olenellus Callavei. 



spine almost to the axis of the glabella just in advance of the neck 

 furrow ; in the double character of the lobes and furrows of the 

 glabella itself, and in the form and position of the eyes. It differs 

 from 0. Kjerulji in its larger size, and more compact habit; in the 

 rapid contraction of the glabella towards the front, in the much 

 greater development of the occipital spine, and in the falcate charac- 

 ter of the terminal parts of the pleurae. 



0. Callavei agrees, on the other hand, with 01. Broggeri in all 

 those features which distinguish the former from 0. Kjerulji ; and 

 differs from it in all those characters which are common to the 

 English and Norwegian forms. In addition, a minor distinction is 

 constituted by the much greater extension of the genal and inter- 

 ocular processes in 0. Callavei than in 0. Broggeri, and a much lesser 

 extension of the great occipital spine. 



The form is dedicated to my friend Mr. Charles Callaway, D.Sc, 

 F.G.S., who was the first to detect organic remains in the Comley 

 Sandstone, and the first to demonstrate the presence of true Cambrian 

 fossils in Shropshire generally ; and whose original and sagacious 

 inference as to the probable pre-Cambrian age of the unconformably 

 underlying rocks the discovery of Olenellus places beyond much 

 dispute. 



In addition to the fragments upon which the foregoing description 

 has been mainly drawn up, a few figures (Figs. 24 and 25) are given 

 on Plate XIV. of younger examples of the species, in which the same 

 characteristic features will be recognized. 



Oleneiliis Callavei occurs in a highly calcareous bed of bright 

 purplish-red calcareous sandstone, or sandy limestone, near the base 

 of the Comley Sandstone (Hollybush) series of Central Shropshire. 

 The figured specimens were all pi'ocured from a single locality — the 

 Comley Quarry — at the foot of the hill of Little Caradoc, near Church 

 Stretton. In this district the Olenellus-hearing sandstone passes 

 down into olive-green felspathic flags, grits, and concretionary shales, 

 and the base of the entire Comley Sandstone series is formed of the 

 well-known Caradoc or Wrekin Quartzite, which reposes iinconform- 

 ably upon the Volcanic Uriconian Group of Callaway. The Olenellvs- 

 beariiig beds are overlain at once by conglomerates, and gritty and 

 quartzose strata, containing abundant fragments of igneous rocks, 

 concretions of carbonate of copper, calcareous bands, and limy 

 nodules ; and these in turn pass up into flaggy shales and quartzose 

 grits, forming the highest visible parts of the Comley series. 



Olenellus Callavei appears to be strictly confined to that part of 

 the Comley series which lies below the conglomerate bands mentioned 

 above ; and its associates include Kutorgina cingiilata, Linnarssonia 

 sagittalis, Hyolitliellus (compare H. micans, Walcott) and Ellipto- 

 cephalus, sp. 



The overlying conglomerates and limestones are distinguished by 

 the presence of a large species of Paradoxides (P. Groomii * sp. nov.), 

 together with forms of Ptychoparia, Obolella, Protospongia, etc. 



^ Faradoxides Groomii, sp. nov. In general form and size intermediate between 



