Palceozoic Bivalved Entomostraca. 395 



and ends in an umbilical depression, sometimes with a small 

 central tubercle ; and numerous fine lines radiate downwards 

 and outwards over this lower part of the sulcus. This inter- 

 esting feature *, belonging to the " muscle-spot," brings 

 Entomis into close relation with other bivalved Entomo- 

 straca, in which the " vascular spot " or radiating group of 

 vessels is present at or near the centre of each valve, where 

 the transverse muscle is attached. Size of valves \^ x ^^ inch. 



5. Entomis Angelini, sp. nov. (PI. XV. fig. 14.) 



This form has been figured by the late Prof. Angelin, of 

 Stockholm, in an unpublished quarto lithographed plate of 

 Upper-Silarian bivalved Entomostraca, presumedly Swedish, 

 and probably from Gothland. This plate was referred to by 

 Dr. Fr. Schmidt in 1873. Our fig. 14 is copied from 

 " fig. 10" of this " Tab. A," which was kindly given to me 

 by Dr. Lindstrom in 1861, but could not be used at that time. 

 The specimen seems to have been figured of the natural size 

 (il X ^ inch), and shows a strongly convex bivalved carapace, 

 impressed across the dorsal region with a curved furrow, 

 dividing the surface into two parts of unequal convexity. In 

 these features it somewhat resembles Kolmodin's Elpe reni- 

 formis (CEfversigt Kongl. Vetensk.-Akad. Forhandl. 1879, 

 vol. xxxvi., 1880, p. 135, pi. xix. figs. 2 a-2 c) ; but the 

 latter is almost equally convex on both moieties of the valves. 



M. Barrande's Elpe innguis f (Syst. Sil. Boheme, vol. i. 

 Suppl. 1872, p. 512, pi. xxvi. figs. 15a-15 e) may belong to 

 the same genus; but Ellje inclioata^ Barr. [ibid. p. 511, 

 pi. xxvi. figs. lOa-lOe), appears to me to be more nearly 

 related to EntomoconchuSj as Barrande at first thought ; 

 indeed he seems to have been very uncertain as to the zoolo- 

 gical placing of these two species. To enable us to catalogue 

 and refer to Angelin's figured Entomis^ I venture to suggest 

 a specific name for it ; and unless our friends in Sweden have 

 already given a name, I propose to dedicate it to Angelin 

 himself, so well known and eminent among paleontologists. 



Tiie relatively large size of the specimens here referred to 

 under the above heading might seem at first sight to separate 

 them from the other fossils described in this paper ; but, in 



* The radiate muscle-spot is referred to at p. 413 Ann. & Mag. 

 Nat. Hist. June 1873, as occurring in Entomis tuberosa ; this should 

 be, as we now see, E. Haswelliana. 



t The Cythere cincimiatiensis, Meek, Geol. Surv. Ohio, vol. i. part 2, 

 1873, p. 158, pi. xiv. figs. 1 a-1 d, closely approximates to E/rf inngtiis, 

 Barrande, though less globose. It is from the Lower Silurian o Cincin- 

 nati, Ohio. 



