Crustacea — Malacostraca. 



81 



of Cambridge. Several forms occur fossil in the Chalk and Crustacea. 

 Tertiaries ; as Falcega Carteri, Grey Chalk, Dover (Fig. 139), and CrALLERY 

 Eosph<Broma Smithii, Eocene, Isle of Wight. jlagt side. 



Wall-cases 

 3. — CuMACEA. The only fossil forms referable to this division are 1^1^' 

 the so-called Ceratiocaris scorpioides and C. elongatus of Peach, from cases 

 the Lower Carboniferous rocks of Scotland. The Cumacea have either 80-86. 

 no eyes or a single eye, whilst a very few have two eyes. They 

 have a small cephalic shield, and a long slender body, with two forked 

 swimming-feet at its extremity. Only the first five segments behind 

 the head carry any appendages ; the other segments have none. 

 The feet all have two branches (an exopodite and an endopodite) 

 like larval Crustacea, and also most Entomostraca. 



Fig. 141. 



Bromilites Zamarckii, Desm. London Clay : Sheppey. 

 Falceocorystes Stokesii, Mant Gault : Folkestone. 

 Eryon arctiformis, Sch.1. Kimeridgian : Solenhofen. 

 Mecochirus longimanus, Schl. Kimeridgian : Solenhofen. 

 Cypridea tuberculata, Sby. "Wealden : Sussex. 

 Loricula pulchella, G. B. Sby. Lower Chalk: Sussex. 



(b) Podophthalma: 1. — Stomatopoda. This type of Crustaceans 

 is one in which the divisions of the body can be very well and 

 distinctly seen. The eyes are stalked ; the carapace is very 

 small; the antennules are branched; the antennae carry a scale 

 at their base. The second maxillipeds are developed into power- 

 ful raptorial organs, having comb-like claws. The free segments 



