200 HYMENOPTERA. 



not been discovered. Should, however, the opinion of Dr. Savage 

 prove to be correct, we may reasonably expect that Labidus may 

 prove to be the male of Eciton. I think it is more probably its 



parasite. 



Genus MYRMECOCYSTUS. 



Myrmecocystus, Wesm. Bull. Acad. Roy. de Brux. v. (1838) 

 p. 766. 



Lucas, Bull Ent. pi. 54 ; Ann. Soc. Ent. Fr. (1855). 



"'The first abdominal segment of one node; the mandibles 

 triangular and much toothed ; abdomen swollen at times like & 

 balloon, and then perfectly transparent. In Mexico called hor- 

 migas mieleras or mochileras, i. e. honey-ants or pouched ants 

 their abdomen containing a sufficiently agreeable honey." 



MYRMECOCYSTUS MEXICANUS. 



Myrmecocystus mexicanus, Wesm. Bull. Acad. Brux. (1838) 



p. 770. pi. fig. $ . 

 Hab. Mexico. 



Only workers of this singular species of Ant are described; they 

 are of two very distinct forms ; the plate which illustrates the 

 paper exhibits the small worker of the ordinary form, but the 

 larger worker is represented with its abdomen swollen into an 

 immense globular receptacle ; this is effected by the distension of 

 the membrane which connects the segments. The account for- 

 warded to M. Wesmael by M. de Norrnann, the discoverer of the 

 >pecies, is, that the latter individuals are inactive, do not quit the 

 nest, and that their sole occupation is to elaborate a kind of 

 honey, which they discharge into receptacles. 



The Cremutoy aster inftatus of this Catalogue, page 136, is a 

 species which probably has workers that perform a similar ope- 

 ration, but in this case it is rendered even more remarkable from 

 the receptacle or laboratory being a swollen bladder-like forma- 

 tion on the metathorax of the insect : this singular apparatus is 

 furnished with a small circular orifice at the posterior lateral 

 angles, from which the saccharine fluid doubtless exudes ; por- 

 tions of crystallized particles are visible within the orifices, and 

 frequently are also scattered over the whole surface of the in- 

 flation ; we may therefore reasonably conclude, that this insect 

 elaborates a suitable and necessary aliment for the nourishment 

 of the young brood. 



Page 36. Formica sericata belongs to the genus Polyrhachis; 

 ^per-imens in the British Museum have been received recently 

 from the island of Aroo (Moluccas;. 



