

XII] PHYLLOPODA 205 



the second antennae and mandibles of the adult ; both are at first 

 placed behind the mouth. 



The Entoinostraca consists of the following Orders : 



Order I. Phyllopoda. 



As the name implies the Phyllopoda (Gr. <v\\ov, a leaf ; 

 a foot) are characterised by possessing flattened leaf-like swimming 

 limbs. Of these there are at least four pairs but there may be 

 many more. The larger Phyllopoda are not uncommon in Britain ; 

 one genus, Artemia, taken at Lymington, flourishes in salt-pans in 

 which the salt is so concentrated as to be fatal to other animals. It 

 can be reared by making solutions in distilled water of the substance 

 sold as " Tidman's sea-salt " of 8 % strength. If a number of such 

 solutions be made, the larvae of Artemia will appear in some of 

 them. These larvae can be fed by making decoctions of fresh green 

 leaves in water. They will if carefully tended grow to maturity. 

 Artemia is devoid of the carapace and has an elongated heart ex- 

 tending throughout the body. Branchipus (Fig. 77) an allied genus 

 occurs in stagnant water, and has been recorded in several localities 

 in the south of England. It is often found in the vicinity of 

 Montreal, in Canada, in the pools of rain water which have 

 accumulated in disused quarries. Apus is another of the larger 

 forms which was formerly found in Britain but has not been met 

 with for some years and is possibly now extinct in this country. 

 It has a large carapace, and its flattened leaf-like appendages are 

 regarded as primitive types of the Crustacean limb from which 

 all the numerous modifications of the higher forms may be derived. 

 Of these, eleven pairs are situated in front of the genital opening 

 and often termed "thoracic," one pair being attached to each of 

 the pre-genital segments of the trunk. Behind the genital opening 

 there are fifty-two so-called " abdominal " pairs of legs, of which 

 several pairs are attached to each post-genital segment except the 

 last two or three. 



The genera Simocephalus and Dapknia, common in ponds and 

 ditches, both in England and America, differ from the foregoing 

 in having fewer segments and in possessing a bivalve carapace 

 which completely encloses the body. The first antennae, or, as 

 they are generally 'called, the antennules, are small and simple, 



