28 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Nov. 20, 



Chelce. — The first pair of limbs arc nearly equal in size ; the inner 

 margin of both the fixed and the movable digit of the chelae is armed 

 with small irregular-sized teeth ; one of the hands is slightly more 

 tumid than the other ; the forearm, or wrist, is armed with a some- 

 what prominent spine on the inner margin, and its distal margin is 

 triangular in outline on the upper surface. The arm is short, straight, 

 and robust (PI. I. figs. 1 & 2). 



Walking-feet (2nd 3rd and 4th pairs). — The three succeeding pairs 

 of limbs are rather slender and compressed, the terminal joint long 

 and tapering (PL I. figs. 1 & 2). 



Fifth pair. — The fifth pair are wanting ; but from the pro- 

 jecting position of their primary or basal joints (well seen in one of 

 the specimens obtained by Mr. Meyer) they may have been modified 

 as in the living species of Portunidce, so as to fulfil the office of 

 swimming-feet. 



Antennae. — The antennas are not preserved. 



I subjoin a list of the principal measurements of R. bispinosa, 

 obtained from the new specimens in Mr. Meyer's collection. 



Length of carapace, from the rostrum to the posterior border, in 

 the largest specimen (PI. I. fig. 1), 1\ inch; breadth to base of epi- 

 branchial spines, 2| inches ; breadth to tips of epibranchial spines, 

 4| inches ; breadth of the posterior border of the carapace, 1 inch. 



Another smaller individual, in which both the epibranchial spines 

 are preserved, also measures nearly 4| inches from tip to tip of spines. 



The figures on the plates are all of the natural size, the restored 

 figures giving the size of the largest specimens in Mr. Meyer's col- 

 lection in which both the spines, the chelae, and the running-legs are 

 preserved. 



Litoeicola*, gen. nov. PI. II. figs. 1-5. 



Carapace about one third broader than long, greatest breadth of 

 carapace between the epibranchial spines. Length of carapace equal 

 to breadth of anterior border; breadth of posterior border equal to half 

 the greatest breadth of carapace. 



Carapace smooth, or nearly so ; anterior angles of carapace trun- 

 cated ; marginal dentations small ; rostrum squarish, bent down- 

 wards ; orbits (and eyestalksf) long. 



Chelae smooth, flattened, of unequal size (smallest in the female?) 

 Legs well adapted for running. 



Underside and abdomen. — At present unknown. 



It affords me no little gratification to be able to add another genus 

 to our small list of Fossil Shore-Crabs. 



In December 1867 I published the figure and description of 

 Gohiocypoda Edwardsi, a new genus of British fossil Shore-Crabs, 

 from the lower Eocene of High Cliff, Hampshire (see Geol. Mag. 

 1867, vol. iv. p. 529, pi. xxi. fig. 1). 



This was the first instance of a fossil Crab occurring, belonging 

 either to the Ocypodidce or to the Grapsoididos (forming Milne- 



* From litus, shore, and coh, I inhabit. 



t Only a trace of what appears to rae to be an ejestalk remains. 



