Syrphidae. 35 



region, and from North America about 730; of these about 38 are 

 recorded as common to both regions. 



The Syrphidae are not specially attacked by parasitic Hymen- 

 optera, but not few cases are however icnown ; I have foimd the fol- 

 lowing (where nothing else is mentioned the record is found in Dalla 

 Torre's catalogue): From Chilosia intonsa 1 have bred a Cryptus sp., 

 one in each pupa; from Platychirus clypeatus (and other species of 

 this genus) Mr. Schlick and I have bred Bassiis spp., one in each 

 pupa, and TricJioste resis glahra Boh., four to five in each pupa; 

 Xanthandrus comtus: Microterys aeruginosus Dalm. (Silvestri, Boll. 

 Lab. Portici, II, 1908); Lasiophthicus pyrastri: Bassus alhosignatus 

 Grav. (Martelli, Boll. Lab. Portici, V, 1911), Bothriothorax californicus 

 How. and Apanteles lineola Curt., the larva of this latter goes as usual out 

 of the Syrphid larva and forms its silky cocoons (Curtis, Farm Insects, 

 1857); Syrphus rihesii: Eucoela crassinervis Westw., Chrysolampus 

 syrphi Ratzeb., Megaspilus syrphi Bouché; Syrphus vitripennis : of this 

 I have bred Bassus sp., one in each pupa; Syrphvs philadelphicus: 

 Pachyneuron syrphi Ashm. ; Syrphus nitens: from this Mr. Schlick has 

 bred Pachyneuron formosum Walk., up to fourteen parasites in each 

 pupa, I have bred from it Trichosteresis glahra Boh., five in each 

 pupa ; Syrphus tarsatus [dryadis) : Bassus arcticus Holmgr. ; Syrphus 

 tarsatus or arcuatus: Pachyneuron groenlandicum Holmgr. (Lundbeck, 

 Vidensk. Meddel, fra Nat. For. København 1896), three in each pupa; 

 Syrphus balteatus: Bassus laetatoriiis F., this species is commonly 

 bred and well known, also Mr. Schlick and I have bred it; one in 

 each pupa. Bassus alhosignatus Grav. (Martelli, Boll. Lab. Portici, V, 

 1911), Homotropus tarsatorius Panz., Pachyneuron formosum Walk., 

 Pachyneuron sp. (Martelli, Boll. Lab. Portici, V, 1911), eight to eighteen 

 in each pupa, Megaspilus syrphi Bouché; Syrphus quadrimaculatus: 

 Pteromalus quadrimaculatus Ashm.; Syrphus sp. : Limnerium clypeare 

 Brisch., Promethes festivus F., Fhygadeuon sodalis Taschbg., Ceraphron 

 ancyloneurus Ratzeb. ; Olbiosyrphus laetus : Bassus alhosignatus Grav. ; 

 Xanthogramma ornatum : Pteromahis punctatus Ratzeb. (Beling, Arcli. 

 f. Naturgesch. 48, 1882), many in each pupa; Mesograpta ohliqua: 

 Hemiteles sy rphicola Ashm.; Volucella sp. : Phygadeuon volucellae Boie; 

 Eristalis tenax: Tropidopria conica F. ; Myiatropa florea: Rhemhohius 

 nigritus Grav.; Myiolepta luteola: of this I once took a number of 

 pupæ some of which were empty; of these latter a couple show^ed 

 by the shape of the hole, that a parasite, probably some Ichneumonid, 

 had escaped from the pupæ. Finally Mr. Schlick has bred from an 

 undetermined Syrphid pupa {Chilosia or perhaps Syritta) Diapria sp., 

 many in the pupa. 



3* 



