250 Prawn Local Name ; Breeding Number of Eggs. 



Within our District prawn is the only local name, though 

 Bell (Brit. Stalk-eyed Crust.) mentions that at Poole diminutive 

 common prawns and allied forms are there sold as " cup- 

 shrimps." Such as we have examined in the fresh condition 

 contained food similar in kind to the shrimps with which they 

 were keeping company. 



Of the ratio of the sexes and their Kent and Essex spawn- 

 ing grounds we have no reliable information. As regards 

 breeding period, this to some extent appears to agree with 

 that of the brown shrimp. In our estuaries they are met with 

 bearing nearly ripe eggs on their swimmerets during May and 

 June. On the Devonshire coast they are got with spawn on 

 the swimmerets from November till June. Hence late autumn 

 may be their time of congress, and the extruded eggs borne on 

 the abdominal region throughout winter and spring, as in the 

 case of the shrimp. 



We have observed that in the prawn there appears to be a 

 relation between size and age to the numbers of eggs carried ; 

 a counterpart to what obtains in the true shrimp. For instance, 

 in 2f inches long specimens we have counted 1,500, and in 

 3j inches examples more than twice that number. According 

 to Thompson,* the eggs primarily are somewhat oval-shaped, 

 becoming rounder as they enlarge. They change from yellowish 

 to reddish-brown, ultimately acquiring a transparent flesh- 

 colour. He traced the several stages after escaping from the 

 egg ; its larval development resembling that of the shrimp, and 

 with successive early moul tings. Warringtonf kept some in 

 an aquarium, and observed that they moulted from the end of 

 May till beginning of September. They ceased to feed before 

 the operation, and afterwards devoured their castings. The 

 period of moulting varied from 12 to 24 days in different cases. 

 He remarks that the prawn's eyes are very brilliant at night 

 and shine out like bull's-eye lamps. 



* Edinb. New Philos. Journ., XXI. (1838), PI. 1. 

 t Ann. and Mag. Nat. Hist., 1855, Ser. 2, IV., p. 247. 



