76 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 79 



Q. arizonica^ has the legs in part lightly clouded, but is otherwise a 

 typical 5"wem-?an«6 (Fitch). 



30. DECATOMA QUERCI-LANAE var. DORSALIS (Fitch) 



Spalangia qucrci-lanae var. dorsalis Fitch, Ann. Rep. New York Agr. Soc, pp. 



81G-817, 1859 ; 5th Rep. Nox. Ins. New York, p. 36, 1859. 

 Decatotna querci-lana-dorsalis (Fitch), Ann. Ent. Soc. Amer., vol. 7, p. 8, 1914. 

 Decatoma querci-lanae Ashmeiad, Trans. Amer. Ent. Soc, vol. 14, pp. 196, 197, 



1887. 



Differs from the lighter form by its smaller size and in having the 

 head always continuously black from vertex to occiput, and the rest 

 of the body generally blacker. 



No such dark forms are known in the female sex. 



Male. — Length, 1.9 to 2.5 mm., mostly intermediate size, relatively 

 slender, colors black and yellow, black predominating; in extreme 

 black specimens, head black except oral area and narrow circum- 

 ocular ring, otherwise degree of yellow variable, the ocular ring 

 sometimes dilating to include cheeks and temples and yellow of oral 

 area extending to occiput behind and up the face to antennal fossae 

 or higher, but vertex almost always entirely black from antennal 

 scrobe to ocular band, black area of vertex always broadly contin- 

 uous with that of occiput, latter also entirely black ; antennae colored 

 as on lighter males, and the females ; pronotum of darkest specimens 

 with an almost square black area full length of median third, and 

 rest of sclerite lemon yellow ; but median black space sometimes not 

 so long as pronotum and not so broad as median third of this segment, 

 and sometimes hind edge of pronotum narrowly yellow or with a 

 somewhat rounded yellow area; on one specimen the lateral thirds 

 black, these separated from mesal black area only by a fine oblique 

 line of yellow on each side; mesothorax usually mostly black, some- 

 times entirely so with only tegulae yellow brown, mesopleura occa- 

 sionally with yellow patches, more often scapulae and axillae in part 

 brown yellow, rarely a yellow line or narrow band in each parapsidal 

 furrow and continuing caudad over lateral thirds of scutel; meta- 

 thorax and propodeum almost always entirely black, occasionally a 

 yellowish patch on metapleura; legs mostly yellow, coxae almost 

 always more or less black, hind pair mostly so, disks of middle femora 

 and tibiae sometimes lightly infuscated, those of hind legs darker 

 still, rarely entirely black, peduncle black, abdomen likewise, fre- 

 quently shading to brown black on ventral half. 



Dimensions of head and funicular segment, and sculpturing and 

 vestiture as in lighter form males. 



Type locality. — New York State. 



Type.— Mule, U.S.N.M. No. 1833 (Dr. Asa Fitch). 



No other type material has been found. 



