94 MB. smith's descriptions of hymenopteeous insects 



The most interesting insect, in a geographical point of view, is 

 undoubtedly a species of Thynnus from Bachian ; this is the most 

 northern range of the genus from its metropolis, Australia, with 

 which I am acquainted. Amongst the Apidce, however, will be 

 found the gem of the collections ; this is a species of Megacliile. 

 Not only is it equal in size to the largest known species oi X:ylocoim, 

 but it is twice the size of the largest previously known species of 

 the genus to which it belongs, and ten times the size of the small- 

 est. This is certainly the finest addition which Mr. Wallace has 

 made to our knowledge of the family Apidce. 



In this paper 191 species are enumerated, of which 132 are new 

 to science, and 59 have been previously described. This fine 

 collection of Hymenoptera is the property of William Wilson 

 Saunders, Esq. 



Pam. FOEMICID^, Leach. 

 Gren. Formica, Linn. 



1. Formica laevissima, Smith, Proc. Linn. Soc. 1859, ii. 138. 

 Hab. Bachian; Aru. 



2. Formica pallida. Smith, Proc. Linn. Soc. 1857, ii. 67. ' 

 Hab. Bachian, Borneo, Sumatra. 



3. Formica subtilis. Capita, thorace, pedibusque rufo-testaceis ; 

 abdomine nigro. ( Worker major) pallida testacea lajvis nitida ; pedibus 

 elongatis {Worker minor). 



Worker major. Length 3i lines. Head rather darker than the thorax 

 and legs ; wider than the abdomen, elongate-ovate and shining ; the 

 mandibles stout, their inner edge with short acute blackish teeth. 

 The thorax much comj)ressed and narrowed behind. Abdomen ovate, 

 black with an aeneous tinge, and sprinkled with pale glittering hairs ; 

 the scale of the peduncle narrow, with its upper margin rounded. 



Worker minor. Length 2 lines. Of a paler colour than the pi-ece- 

 ding ; the antennae very slender, and longer than the body ; the legs 

 very long, the posterior pair nearly twice the length of the body ; the 

 scale of the peduncle conical. 



Hab. Bachian. 



4. Formica vitrea. F. nigra, nitida; mandibulis tarsisque rufo- 

 pallidis ; squama quadrata. 



Worker. Length 2 lines. Jet black, smooth and shining ; head a little 

 wider than the thorax ; eyes ovate, placed rather high on the sides of 

 the head ; the antennae longer than the thorax, the flagcHum slightly 

 thickened towards the apex; the mandibles pale rufo-testaceous. 

 Thorax narrow, compressed behind and strangulated at the base of the 

 metathorax; the scale of the abdomen compressed, quadrate, and 



