66o FAUNA HAWAIIENSIS 



(2) Pentarthron flavtim, sp. nov. 



Female, entirely flavous, the head in life probably still paler, the eyes and ocelli 

 red, lateral ocelli near the eye-margins. 



Antennae six-jointed with a ring joint, the club solid, and equal in length to 

 the pedicel ring joint and funicle together, the two funicle joints in some aspects appear 

 not very different from one another, the scape with its basal pedicel is a good deal 

 longer than the pedicel and funicle joints together. The mesonotum has a bristle 



Pentarthron Jlavum ? . 

 Antenna in two rather different aspects. 



in front on each side, and another near the posterior angles, the scutellum one on each 

 side near the posterior margin. The axillae encroach greatly on the parapsides of the 

 mesonotum, so that the latter are subsecuriform, being dilated in front and sublinear 

 posteriorly. Abdomen equal in length to the head and thorax together, the ovipositor 

 not, or hardly, exserted. 



Wings hyaline about 7 or 9 more prominent hair lines, between which are 

 a number of others closer together, or more confused, or incomplete. Length % -8 mm. 



Hab. Oahu, Honolulu. 



Fam. MYMARIDAE. 



The Mymarids are a very distinct group of Hymenoptera, to be ranked as 

 a superfamily more distinct from any one other than, for instance, is the superfamily 

 Apoidea from the Sphecoidea. They show affinities with the Proctotrupoidea, 

 especially with the Diapriidae, and also with the parasitic Cynipoidea. Of the Chalcid 

 series they appear more nearly related to some Eulophidae and Trichogrammidae, but 

 the affinity is very remote. 



The endemic Hawaiian species are probably confined to the genus Polynema, but 

 some species introduced either casually, or purposely for economic reasons, are also 

 present, and now more numerous individually than the native forms. I have not 

 thought it advisable at present to describe specimens from the intermediate islands, 

 which may represent mere varieties of those occurring on Hawaii and Oahu. Con- 

 sidering the difficulty of differentiating species from the different islands in the case of 

 larger insects, it may naturally be expected that in minute parasitic Hymenoptera these 

 difficulties will reach a climax. Various species, of which only one sex is known, 

 I have also left undescribed at present. 



