30 FOSSIL MALACOSTRACOUS CRUSTACEA. 



nuchal furrow strongly marked, and its lateral portion extending furtlier forwards than in 

 most of the species. Abdominal segments more finely and evenly granulated than the 

 carapace. Professor j\l'Coy states that " the last segment and middle tail-ilap have a 

 mucli coarser, flattened, or squamous tuberculation ^ the transverse sutiu'e of the outer 

 tail-flap strongly marked, from the great thickness of the basal portion ;" of this I am 

 unable to speak from my own observation, as in all the specimens I have seen these parts 

 are wanting or im[)erfect. The anterior legs are very unequal, almost as much so as in 

 //. lont/itiiana. The ai"m is tuberculated, with a row of a few large tubercles on the upj)fr 

 side ; it is much widened towards tlie distal extremity, where it is about half as broad as 

 it is long ; both the hands are very much flattened, the larger twice as long as it is broad, 

 tuberculated, and armed with a row of large tubercles along the inner edge ; the fingers 

 about as long as the hand, the iumioveable finger almost falcate, depressed in the middle 

 throughout its length ; the prehensile mai-gin strongly tuberculated ; the immoveable 

 finger broad and curved, but less so than the other, and tunned with similar tubercles. 

 The smaller hand roughly granulated, the inner edge with a scries of tubercles as in the 

 larger ; the fingers twice as long as the hand, very slender, the immoveable one much 

 flattened and sUghtly curved ; the moveable one less flattened, smaller, and also slightly 

 curved. 



Length of the whole body G"o inches; length of the carapace, from the mai"gin 

 of the orbit, 2-5 inches; breadth 1-G inch; length of rostrum GO iucli ; length of larger 

 hand and fingers 4-2 inches; breadth 1'5 inch; length of smaller hand, with the fingers, 

 5"2 inches, the fingers occupying more than two thirds of the length. 



From the upper Greensand in the Isle of Wight, and near Devizes, in Wiltshii-c. 



Oh. This fine species was first discovered by Mr. Saxby, in the upper Greensand at 

 Bonchurch, in the Isle of Wight, and described in the ' Annals of Natural History' by 

 Mr. M'Coy, who dedicated it to the discoverer. The large specimen figured in Plate VIII 

 is in Mr. Cunuington's collection, and is from the Greensand of Wiltshire ; and the hands 

 represented in the same plate belong to another fine example, collected by Mr. Norman, of 

 Ventnor, and now in the British Museum. With the exception of //. scahra, it is the 

 largest species of the genus with which we are yet acquainted. 



Genus — AsTACODEs, BelL 



ASTACODES EALCIFER, Sp., Pllillips. Plate IX, figS. 1 6. 



Myekia falcifeu, Phill. 



Of this remarkable species scarcely sufficient data exist for a satisfactory description ; 

 yet the remains which have come into my hands indicate not merely the specific but the 



