1374.] Wood-Mason — On Trictenotoma Cliildrenii. 181 



further stated that the Astactts Zaietccus of Willenioes v. Suhm was no 

 Astacid at all, but represented a new and very remarkable genus of ThalaS' 

 sinidce, which he proposed to designate Thaumastocheles : in this species, 

 particularly, the caudal ' swimmeret' had not the terminal plate of its outer 

 branch transversely jointed as in all true Astacidce ; he was glad to find 

 that M. Alph. Milne-Edwards, the eminent carcinologist of France, had 

 expressed a similar opinion with regard to its systematic position, in a" Note 

 0Yii\\Q JSTeph'o^psis Steivarti of Wood-Mas./' published in the last number of 

 the ' Annales des Sciences Naturelles.' 



Mr. Wood-Mason also exhibited specimens of Trictenotoma Childrenii^ 

 Gray, and read the following note thereon. 



Note on Trictenotoma Childrenii, Gray. 



So far as I have been able to discover, one additional species only of 

 the very anomalous family of coleopterous insects, TrictenotomidcB, of which 

 T. Chihhenii, Gray is the type, has been described since Professor West- 

 wood published in his ' Cabinet of Oriental Entomology'* the results of his 

 dissections of the three species known to him, viz., of T. Childrenii, Gray, 

 T. TempJetonii, Westw., and T. aenea, Parry. Of the first-named I have 

 recently received two specimens ( $ ) collected at Samaguting, in the Naga 

 Hills, by Captain J. Butler, a third ( $ ) captured by Major H. H. Godwin- 

 Austen in the Dhansiri Valley, and a fourth ( S ) taken by one of the 

 collectors of the Indian Museum at Johore, in the Malay Peninsula. 



This species having been incorrectly described by Dupont,t whose 

 specimen had most likely become stained by the exudation of fatty matters 

 from the body of the insect itself, after death, or by prolonged immersion in 

 alcohol in company with other objects, as " couverte en dessous d' un vil- 

 losite jaune verdatre," it may be worth while to correct the mistake. 



The whole of the ventral surface of the insect, in both sexes, from the 

 extremity of the abdomen to the very tips of the triangular processes that 

 lie in front of the eyes and bound the labium Qmentum of West wood), the 

 femora to their distal ends, and the narrow inflected portions of the elytra 

 are clothed with a most delicately pure ashy-grey pubescence, wanting only 

 on the mesosternal process, which appears to be normally shining-black, 

 and on the middle of the posterior margins of the abdominal segments, from 

 ■v^hich it has been removed by friction ; the pubescence on the labium and 

 the fringe of hairs on the fore margin of the prosternum alone being stained 

 with very pale luteous ; the anterior and posterior faces of the tibiae, espe- 

 cially of the two anterior pairs, are also slightly pubescent. 



The distribution of the four described species is as follows : — 



T, Childrenii. Hab. Assam ; Tennaserim coast ; Johore ; Java, 



* Op. Cit., p. 47, PI. XXIII. t Mag. de Zool., pi. 35, 1832, 



