1 823.] Doctrine of Affinity and Analog^. 4fi§ 



calculated to masticate, but more grossly, a harder substance 

 than what is submitted to the action of the mandibles of Me/o- 

 lontha F. In a specimen of Areoda I found adhering to this 

 molary plate, a substance resembhng the pollen of flowers, 

 which may hence be conjectured to be the food of that genus.* 



From this account it seems I think evident, that a modifica- 

 tion of the three kinds of teeth of vertebrate animals is to be 

 found in these tribes as well as the Orthopteray in which Mar- 

 celle de Serres detected them ; for we find the incisores at the 

 apex of the mandible, the molares at its base, and the laniarii at 

 the apex of the maxillse ; though with respect to these last, I 

 believe their primary use in very many insects is to hold the food 

 for the action of the mandibulae. 



MiMELA ChINENSIS. 



Long. corp. lin. 9. Habitat in China. Ex Mus. D"* 

 Crane. 



Corpus glaberrinium, luteo-virens, colore sub luce mutabili, 

 subtus cupreo tinctum. Capw^ supra antice punctis confluenti- 

 bus rugulosum, postice punctis sparsis conspersum, interque 

 puncta creberrima minutissima, vix sine lente forti conspicua, 

 subtus fulvum. Antennce fulvae. Thorax punctis sparsis punc- 

 tulis minutissimis interjacentibus ut in capite. Elytra subru- 

 gosa, puncto-striata : striis intermediis per paria ordinatis, inter- 

 stitiis punctatis et punctulatissimis ut in thorace, &c. apice 

 gibba. 



The insect I shall now describe is of a different order ; and 

 though it does not so strikingly assume the characters of another 

 tribe or genus ; yet, as it appears to partake of those of both 

 Agrion and Lestes, exhibiting the general appearance and wings 

 of the former, with some diagnostics of the latter, it seems not 

 improperly introduced. 



Agrion Brightw^elli. 



Nigrum : alis basi, in altero sexu apice macula, sanguineis. 

 Long. Corp. unc. 2-^. Expans. alar. unc. 2|.. Habitat in 

 Brasilia. Ex. Mus. D. Brightwell. 



Corpus nigrum, sub sole splendore obscure metallico subnitens. 

 Caput subpilosum. Truncus brunneo-niger, supra lineis tribus 

 longitudinalibus, intermedio elevato, nigris, sub alis primoribus 

 strigis tribus obliquis, superiori obsoletiori, paUidis. Al(C sub- 

 hyalinse, basi Isete sanguineae, posticis apice macula subrotunda 

 ejusdem coloris. Stigma nigrum oblongo-quadratum. Abdomen 

 elongatum, tenue, transversim rugulosum, basi et apice subin- 

 crassatum. /orceps anahs rectus ? inferiorisubincurvo. 



* Since this paper was written, I met accidentally with a passage in Cuvier's jina- 

 tomie Comparte (iii. 321 — .), by which it appears that he had observed in the mandi- 

 bles of the larva; of the Lncani " vers leur base, una surface molaire plane et strtte j" 

 but he does not appear to have noticed this structure in any perfect insect. 



