52 me. smith's catalogue or hymenopterous insects 



far as the stigma, beyond which they are milky-white ; the abdomen 

 obscurely rufo-piceous at the base. 

 Hab. Malacca (Mount Ophir). 



9. Trigona fimbriata. T. capite thoraceque femoribus et abdomine 

 basi testaceo-rufis ; tibiis tarsisque intermediis et posticis nigris. 



Worker. Length 3£ lines. Head rufo- testaceous, the face covered with 

 very short ochraceous pubescence, and sprinkled with longer stiff 

 black hairs ; the colour and pubescence of the thorax are similar to that 

 of the head, but the disk is of a rather darker colour, and the black hairs 

 are longer and more rigid ; the intermediate and posterior tibiae, and 

 the basal joints of their tarsi, black, the former densely covered with 

 black pubescence, and the latter thickly fringed with the same, the 

 posterior tibia; being very broadly dilated towards their apex ; the 

 wings hyaline, their nervures bright ferruginous. Abdomen: the two 

 basal segments rufo-testaceous, their apical margins, as well as the 

 whole of the following segments, nigro-fuscous. 



Hab. Singapore. 



Earn. FOKMICLD^E. 



Before entering upon the descriptions of the highly interesting 

 collection of Ants made by Mr. "Wallace in Borneo, Malacca, and 

 Singapore, a few observations may not be out of place. I am 

 perfectly aware, that in treating upon this family, I can only 

 achieve a very partial success ; our present knowledge, scanty as 

 it is, convinces me that it is simply an impossibility to assimilate 

 the sexes of the exotic Ants correctly, without positive observation 

 of their oeconomy. The sexes of some species, there can be little 

 doubt, at present form the types of apparently very distinct 

 genera ; such indeed are the eccentricities of form in the exotic 

 species, as to outstrip even the widest bounds hitherto conceived 

 to be necessary to allow, for varieties in form, size and colour. A 

 single instance will amply confirm this observation. In the third 

 volume of the ' Transactions of the Entomological Society,' I de- 

 scribed eleven species of the genus Pseudowiyrma ; of one of these 

 I had the opportunity of describing the three sexes, taken in their 

 formicarium by Mr. H. W. Bates, in Brazil. This species, Fseudo- 

 myrma cephalica, exhibits such a remarkable difference of form in 

 the male, female and worker, that, had they not been obtained in 

 the manner stated, I should unhesitatingly have removed the sexes 

 into two distinct genera. In the male and Avorker the head is of 

 the ordinary form and proportion, but that of the female is as long 

 as the thorax, with the sides parallel ; it is in fact, if I may use 

 the term, so disproportionate, that no one, I imagine, could have 



