H. Woodward — New British Fossil Crustacea. 555 



furrow," divides it down the centre for about one-fourth of its entire 

 length, thus separating the anterior parts into two equal lobes ; here 

 the median fuiTow diverges right and left in a crescent-shaped curve, 

 and unites with the cervical furrow, leaving a small elevated median 

 area (cardiac region?), which contracts rapidly backwards and is 

 then prolonged as a narrow dorsal ridge — dividing the two ' elytra '- 

 like lobes — to the posterior border. The anterior and expanded end 

 of this dorsal ridge is ornamented on either side, at its union with 

 the cervical furrow, by two small crescent-shaped lobes. 



The surface of the carapace is everywhere smooth and devoid 

 alike of tubercles and puncta. 



2. Cyclus torosus, H. Woodw., sp. nov., PI. XXIIL, Fig. 4 and 4«. 

 The buckler of this species is nearly circular, and is four lines in 



diameter. Its dorsal line (viewed in profile) is very tumid, and is 

 elevated two lines above its border (see Fig. 4(7.). The cervical 

 furrow divides the carapace — ^transversely — into two nearly equal 

 parts (in this respect offering a marked contrast to C. hilohatus) ; the 

 anterior moiety is divided into eight lobes, and the posterior 

 into three. A narrow slightly flattened border appears to have 

 nearly — if not quite — surrounded the shield.^ 



In front of the carapace is a median, somewhat triangular, lobe, 

 having its rounded apex directed backwards ; this is flanked on either 

 side by two nearly round lobes, two placed subcentrally and two 

 near each latero -anterior border. Uniting these five anterior lobes 

 with the cervical furrow are two lateral five-angled lobes, and a 

 central seven-angled (cardiac?) lobe or area. Behind the cervical 

 furrow a dorsal ridge, of marked elevation, divides the posterior 

 half of the carapace into two rounded lobes, which nearly unite 

 behind — being only separated by a narrow dorsal ridge — but are 

 widely separated in front, not only by the interposition of the dorsal 

 ridge, — which expands like the head of a pillar before reaching the 

 cervical furrow, — but also by the intercalation of two narrow lobes 

 or ridges on either side of the expanded dorsal ridge. The even 

 contour of the carapace is only markedly interrupted by a greater 

 degree of prominence in the dorsal ridge just where it expands. 

 The lobes are all roundly tumid, and, like the preceding species, 

 almost smooth. Cyclus torosus was obtained from the Carboniferous 

 Limestone of Little Island, Cork, by Mr. Joseph Wright. 



3. Cyclus Wrightii, H. Woodw., sp. nov., PI. XXIIL, Fig. 5 and 5a. 

 This well-preserved form (which we have named in honour of the 



discoverer, Mr. Joseph Wright, of Belfast, who has devoted much 

 time and attention to the investigation of the fossils of the Car- 

 boniferous Limestone of Ireland) was procured from the Limestone 

 of Little Island, Cork.^ It is oval in form, being 2f lines in length, 



1 Several of these forms may have heen destitute of a rim in front. See Salicyne, 

 Figs. 7 and 8. 



^ Another specimen, obtained by Professor Harkness from the Carboniferous Lime- 

 stone of Keisley, near Appleby, Westmoreland, appears to be referable to this species, 

 but the intractable nature of the matrix renders it impossible for me to work it out 

 satisfactorily. See Prof. Harkness's paper, Quart. Journ. Geol. Soc, 1865, vol. xxi., 

 p. 243, etc. 



