86 
2. Estheria tetracera, the Limnadia tetracera of Krynicki. 
3. Estheria Dahalacensis, Straus Durckheim. 
To these three species I now propose adding six others, all in the 
collection of the British Museum. 
Legion BRANCHIOPODA. 
Order PoyLLopopa. 
Family Lrmnapiap2&. 
Animal almost entirely enclosed within a buckler or carapace re- 
sembling exactly a bivalve shell. Feet all branchial; from eighteen 
to twenty-seven pairs in number. Antenne four pairs; the two 
superior used as organs of locomotion. Eyes two; closely approxi- 
mated. 
Genus Lrmnap1a, Brongniart. 
Carapace very large in proportion to the size of the animal, which 
appears not to fill much more than half of it. Head small, and having 
a little behind the eye a small pear-shaped body on its dorsal margin. 
Caudal segment truncate and terminating in two diverging lamelle, 
ciliated on their under margin. Small antennz club-shaped. Jaw 
foliated. Carapace beautifully transparent, of a whitish colour and 
very thin and delicate. Valves nearly quite smooth or only showing 
two or three slight concentric ridges on their anterior margin, and 
when highly magnified, numerous very minute dots or puncturations. 
The avimals swim on their back, and no males have ever as yet | 
been observed. 
Sp. 1. Limnapia Hermanni. (PI. XI. f. 1, 1a, 14, Le.) 
L. Hermanni, Ad. Brongniart, Mém. du Mus. d’ Hist. Nat. vi. t. 13. 
f. 1-2, 1820. Desmarest, Consid. gén. sur les Crust. 379. t. 56. f. 1, 
1825. Latreille, Cuv. Régn. Anim. iv. 173, 1829. Bosc, Man. d’ Hist. 
Nat. des Crust. ii. 236, 1830. Guérin, Magaz. de Zool. Class 7. t. 21. 
f. 12, 1837. Lamarck, An. sans Vert. 2nd edit. v. 185 (note). M. Ed- 
wards, Hist. Nat. Crust. iii. 362. No. 1. Cuv. Régn. Anim. edit. 
Crochard, Crustacés, t. 74. f. 1, la. 
Carapace-valves ef a rounded oval form, and permitting only the 
terminal branches ‘of the large antennz and the tips of the caudal 
lamellze to pass beyond their margins ; antennules of the length of the 
peduncles of the large antennz, club-shaped and crenulated on their 
upper edge ; large antennze nearly half as long as the body, and having 
in each branch 12 joints ; feet 22 pairs in number ; caudal lamelle of 
considerable length ; carapace of a clear transparent white colour, and 
nearly quite smooth on its surface. On the anterior half we see two 
or three concentric striz or rather delicate ridges running parallel 
with the lower margin, and when examined by a microscope of con- 
siderable power, we can detect the whole surface of the valves covered 
with numerous minute dots or puncturations. These do not appear 
raised, but as if they were mere opacities in the otherwise clear 
transparent shell. 
