328 BRITISH ENTOMOSTRACA. 



The genus Lernentoma was first established by Blain- 

 ville in his monograph of the Lerneadae, in the ' Journ. 

 Phys.,' 1822, to contain those Lerneae which, as in Chon- 

 dracanthus, were distinguished by their having processes 

 or appendages taking the place of the thoracic feet, but 

 having long, club-shaped, oviferous sacs, 



Oken, in his ' Lehrbuch der Naturgeschichte,' 1815, 

 had placed the several species belonging to Lernentoma 

 ill his genus Anops ; but as that genus is loosely charac- 

 terised by him, and embraces several species belonging 

 not only to different genera, but even to different tribes, 

 I have preferred adopting that of Blainville. Lamarck, 

 in his 'Hist. Nat. An. sans Vert.,' first edition, iii, 1816, 

 places them in his genus Entomoda ; but as that genus 

 embraces also several species belonging to different fami- 

 lies, though it likewise has the precedence in time, I con- 

 sider the more restricted and better-defined genus of 

 Blainville as worthy of preference. Most authors, how- 

 ever, have described the various individuals belonging to 

 Lernentoma as Chondracanthi. 



1. Lernentoma cornuta. Tab. XXXV, fig. 2. 



Lern.ea cobnuta, Midler, Zool. Dau., i, t. 33, f. 6; Enc. meth., 



t. 78, f. 1. 

 Entomoda coknuta, Lamarck, Hist. Au. s. Vert., iii, 685. 

 Anops coknuta, Oken, Lehrbuch tier Naturg., iii. 

 Lernentoma coknuta, Blainville, Journ. Phys., xcv, 441, No. 6. 

 Chondkacanthus coknutus, Cuvier, Regne An., iv, 258. 



— Nordmann, Mik. Beitr., ii, t. 9, f . 5, 6 (?) . 



— M. Edwards, Hist. Nat. Crust., iii, 



500, No. 1. 

 Horned Lekn.ea, Shaw, Naturalist's Miscellany, viii, t. 295. 



Character. — Female. Head oval, rather elongated. 

 Antennae flattened, of considerable size, and projecting. 

 Thorax elongated, club-shaped. Anterior portion narrow 

 for about a third of its length ; the other two thirds much 

 broader, and terminating posteriorly in two sharp lateral 

 tubercles of moderate length, and a middle one represent- 



