MEGALOBLATTA. 57 



This genus is a magnificent Central- American type, and is of great interest on account 

 of its affinities. 



It resembles the Periplanetinse, especially the genus Periplaneta, in the produced 

 bilobed supra-anal plate and in the very long cerci. In the shape of the last segments 

 of the abdomen, which are not acute at their angles, the short spines to the femora, 

 and the black-violaceous colour of the pronotum and elytra, Megaloblatta approaches 

 Deropeltis, the colour being quite typical of that genus and foreign to the other American 

 Blattidse. In other respects Megaloblatta imitates in a very remarkable manner the 

 larger species of the genus Blabera : in its gigantic size, the approximated eyes, the 

 very large and wide elytra having a very broad marginal field, and, what is very striking 

 indeed, in the claws being destitute of an arolium — the latter character appearing here 

 as if for the sole purpose of imitating the Blaberinae ! 



This mimicry is carried to such an extent that at first sight it is very easy to mistake 

 a Megaloblatta for a Blabera, The resemblance, indeed, is continued even to the less 

 apparent characters, as the loss of the arolia and the arrangement and scarcity of the 

 spines of the femora. It is only by an examination of the characters of the abdomen 

 (unspined angles of the segments, long anal plate, very long cerci) that the real position 

 of Megaloblatta can be ascertained. 



l. Megaloblatta rufipes, Dohm. (Tab. V. figg. 15-17.) 



? Blabera regina, Saussure, Miss. Scient. Mex., Orthopt. p. 116. 10 (<?) (1870). 

 Megaloblatta rufipes, H. Dohrn, Stett. ent. Zeit. 1887, p. 409. 2(d). 



<$ . Tota nigra, pronoto et elytris leviter violaceo-nigris. Caput rotundatum, oculis invicem sat propinquis. 

 Pronotum densissime punetulatum, disco nitidulo, minus dense et fortius punctato, lateribus rugulosis, 

 postice carinulatum et in longitudinem striolatum. Mesonotum margine postico membranaceo ; appen- 

 dices membranacei meso- et metanoti graciles, elongati. Elytra immensa, fusco-nigra, subviolascentia. 

 Alse fulvo-fuscse, margine anteriore et apicali obscuriore ; campo anali pallidiore, nebuloso. Femora ante- 

 riora subtus in margine antico medio spinis 2-3, in margine postico spina prseapicali armata ; femora 

 intermedia et posteriora subtus margine antico dimidia parte basali inermi ; intermedia 4 : 3, posteriora 

 6 : 4, spinosa. Abdomen politum, utrinque maculis submarginalibus runs. Segmentum penultimum 

 angulis late rotundato-productis. Lamina supra-analis retro attenuata, rotundata, anguste incisa. Lamina 

 infra-genitalis parva, rotundata, quam ultimum segmentum baud angustior. Segmentum 5 m basi rufeseens. 

 Cerci laminam supra- analem plus duplo superantes. 



Long. 51 ; elytr. 73, pronot. 15-25, latit. pronot. 22 millim. 



Larva, S (fig. 17). Nigra, nitidissima, elliptica, deplanata. Tborax confertim punctulatus. Pronotum semi- 

 orbiculare, margine postico leviter arcuato, angulis lateralibus subrectangulis, acutis. Meso- et meta- 

 notum postice carinulata, processubus membranaceis nullis. Abdomen nitidum, subtiliter punctatum, 

 segmentis 2°-4° utrinque macula lateritia ; segmenta 5 m -7 m coriacea, vix punctata, plicato-corrugata : 

 4 m utrinque angulatum ; 5 m magnum, marginibus lateralibus lamellaribus, valde reflexis, angulis leviter 

 hebetatis ; 6 m angulis acutis. Venter basi rufeseens, utrinque depressione grandi rotundata. Lamina 

 infra-genitalis apice subincisa. Caput et lamina supra-analis ut in imagine ; cerci breviores. 



Long. 44 ; pronot. 11-5, latit. pronot. 18 millim. 



Hab. Guatemala, San Juan in Vera Paz {Champion) ; Panama (coll. Brunner). — 

 Colombia, Medellin ; % Beazil. 



biol. cente.-amek. Orthopt., October 1893. ii 



