THE 



GEOLOGICAL MAGAZINE. 



NEW SERIES. DECADE II. VOL. V. 



No. VII.— JULY, 1878. 



OI5,IC3-I3^Jk.Xj ^^ISTZOXjDBS. 



L — On a New and Undescribed Macrouran Decapod Crustacean, 

 FROM the Lower Lias, Barrow- on -Soar, Leicestershire, etc. 



By Henry Woodward, LL.D., F.E.S., F.G.S. ; 



of the British Museum. 



(PLATE VII.) 



IN my third Eeport "on the structure and classification of the 

 fossil Crustacea," presented to the Geological Section of the 

 British Association, at their Meeting in Dundee,^ 1867, I stated that 

 a new Crustacean had been obtained, in 1858, by Sir Philip Grey- 

 Egerton, Bart., M.P., F.E.S., from the Lower Lias of Barrow-on- 

 Soar, Leicestershire, by whose kindness it is now preserved in the 

 British Museum : and also that another specimen, from the Lower 

 Lias of Somersetshire, belonging evidently to the same species, had 

 subsequently been found by Mr. Charles Moore, F.G.S., at Bath. 

 The specimen from Barrow-on-Soar (the impression and counter- 

 part of which is contained in two blocks of Blue Lias Stone) 

 exhibits on the surface of the slabs, the entire carapace, the eye, 

 antennae, the five ambulatory thoracic feet ; but in this specimen the 

 abdominal somites and caudal appendages are entirely wanting ^ 

 (See PI. VIL Fig. 1.) 



Mr. Moore's specimen, though rather less well preserved, exhibits 

 the carapace with the antennee ; the walking limbs are displaced and 

 expose the thoracic apodemata to which the branchiae and the coxal 

 joint of each limb were attached. The six abdominal somites are 

 also seen, but the caudal plates are only very imperfectly preserved 

 (See Plate VII. Fig. 2.) 



The carapace of this Crustacean evidently was extremely thin and 

 much less chitinous than in the genera Ager- and Penceus ; it was 

 therefore more easily destroyed or distorted. In Fig. 1, the crumpled 

 and wrinkled appearance of the carapace is well shown. In Fig. 2, 

 the test is less well preserved, but near the posterior border there 

 is evidence to show that the surface was finely granulated (not 

 punctated as represented by the artist in the Plate). The dorsal 



1 See British Association Eeports for 1867 (1868), p. 44. 



2 The abdominal somites have been added by the artist in outline to Fio-. 1 

 PI. VII. merely to indicate their normal position ; they are wanting in this speci- 

 men, and although present in Mr. Moore's Crustacean from Bath (Fig. 2. PI. VII.), 

 they are displaced. 



DECADE II. — VOL. V.— NO. VII. 19 



