82 PROCEEDINGS OF THE NATIONAL MUSEUM vol.. 93 



No attempt is made to separate Aplomya affinis from A. estigmen- 

 ensis in the key. This is another example of the resemblance of 

 species between the Nearctic and Palearctic realms. The species 

 A. estigmenensis, as represented by the type material, is distinct from 

 A. affinis on both adult and puparial characters. There is, however, 

 no proof that A. affinis does not occur in North America. Sixteen 

 specimens collected at North Saugus, North Andover, and Melrose, 

 Mass., former liberation points of gypsy moth parasites, favor to some 

 extent the characters of A. affinis. The suggestion is offered that the 

 European species might have been accidentally established in this 

 country while gypsy moth parasites were being imported. The other 

 possibility is that more Nearctic material may indicate a greater 

 intergradation of the adult characters. Arctia caja (Linnaeus) and 

 Phragmatobia fuliginosa (Linnaeus) have been reported as being 

 Holarctic in their distribution. They are of doubtful Nearctic occur- 

 rence, as they are represented by varieties that do not occur in the 

 Palearctic realm. The close resemblance of the hosts may have 

 allowed for a closer parallel development of the parasites than in 

 some of the other cases where similar superficial resemblance of the 

 parasites has been noticed. 



Male always with three and occasionally with four, female with 

 three and usually additional reclinate prevertical bristles and hairs; 

 frontal bristles consistently more numerous in the males. Fourth 

 vein of wing with an indication of a fold or an appendage, usually 

 with a very small stump, especially in the females. Abdomen as well 

 as thorax more noticeably pollinose than in Aplomya estigmenensis ; 

 dorsal vitta present on second segment and obscurely indicated on 

 segments 3 and 4, especially in males; usually but not always with 

 four marginal macrochaetae on second segment; usually with sev- 

 eral discal macrochaetae and bristles on second and third segments. 

 Otherwise the description is much the same as for A. estigmenensis. 



Distribution. — Europe, extending northward to southern Sweden 

 and Finland. 



Hosts. — The published host list is an extensive one. Baer and 

 Lundbeck list (the first six are also listed by Bezzi and Stein) : Por- 

 thetria dispar (Linnaeus), Satumia pavonia (Linnaeus), Pachytelia 

 mllosella (Ochsenheimer), Acronicta alni (Linnaeus), Satumia pyri 

 (Schiffermuller), Arctia caja (Linnaeus), A. hebe (Linnaeus), A. 

 viilica (Linnaeus), Vanessa wrticae (Linnaeus), Orgyia gonostigma 

 (Fabricus), Dasychira pudibunda (Linnaeus), Malacosoma neustria 

 (Linnaeus), Dendrolimus pirn (Linnaeus), Phragmatobia fuliginosa 

 (Linnaeus), Acronicta tridens (Schiffermiiller) , Taeniocampa incerta 

 (Hufnagel) questionably listed by Baer, Lymantria monacha (Lin- 



