HOMOLOPSIS. 23 



Species unica. Homolopsis Edwardsii, mild. Plate V, figs. 1, 2. 



Descr. Carapace rather longer than it is broad, everywhere granulated ; the regions 

 and their lobes very distinct and strongly tuberculated ; the gastric region broad, the 

 anterior portion, comprehending the epi-, proto-, and meso-gastric lobes, forming on each 

 side a nearly circular area, furnished with five tubercles, and separated from the meta- 

 gastric by a well-marked furrow ; the metagastric lobe has three tubercles disposed in an 

 equilateral triangle; its anterior process extends to just behind the front; the hepatic 

 region is very small on the upper surface, and has a single tubercle ; the lateral portion 

 extends broadly downwards to the pterygostomian process, where it has a strong, obtuse 

 carina ; the urogastric is linear, and has a few small, inconspicuous tubercles ; the 

 epibranchial lobe is very convex, and has a large, strong, and prominent tubercle standing 

 outwards on the latero-anterior margin of the carapace ; the mesobranchial has a single 

 tubercle ; the metabranchial lobes very large, roughly granulated, without tubercles, of a 

 somewhat triangular figure, the lateral boundary extending forwards to half the length of 

 the carapace ; a very distinct sulcus separates each metabranchial from the anterior 

 branchial lobes and from the gastric region, the two meeting in an angle at a short distance 

 from the posterior margin. The gastric region regularly pentagonal, with a single 

 tubercle. The nuchal furrow distinct and deep. The front is small, with a small tubercle 

 on each side, and its apex incurved to meet the epistome. The orbits nearly round, open 

 beneath, with a triangular fissure above near the external angle, exterior to which is a 

 large, strong spine ; the antennary fossae small, oval ; epistome large, irregularly penta- 

 gonal, with a strong, transverse carina. The broadest part of the carapace is at the 

 anterior and lateral angle of the metabranchial lobes. 



Length of the carapace, 0*10 inch; breadth, 0"9 inch. 



From the Gault at Folkestone and the Greensand at Cambridge. 



Obs. The affinity of this species to Homola was first noticed by Mr. Carter, of Cam- 

 bridge, who had applied to it in his own cabinet the generic name which I have adopted- 

 It bears a strong general resemblance to the genus Dromilites, described in the former 

 part of this monograph ; but its relation to the Bromiadce is more apparent than real. 

 Whether it may be considered as in any way osculant between these two families, or 

 as, in some degree, confirmatory of an opinion which I have long entertained, that the 

 distinction between the Dromiadge and Homoladse is not borne out by the natural relations 

 of the genera composing the two groups, I must leave with this mere suggestion. 



The remarkable breadth of the metabranchial lobes is the character which gives it the 

 greatest prima facie likeness to Dromilites; but its essential characters, and in particular 

 the absence of all puncta for the insertion of hairs on the carapace, obviously remove it 

 from that genus. 



