588 Syrphidae. 



cross-vein is placed well after the middle of the discai cell, it is al- 

 most not oblique; the basal part of the radial vein with few, fine 

 bristles; there is an indistinct stigmatical cross-vein, Squamulæ very 

 narrow, thoracai squamula with somewhat short, branched hairs, alar 

 squamula with quite short, curiously flattened hairs. Plumula wanting. 



The larva of C. conopsoides was observed by v. Roser (Wiirttemb. 

 Gorr. Bltt. 1834, 267). Leon Dufour describes and figures the larva 

 and pupa (Ann. de la Soc. Ent. de Fr. 2, V, 1847, 19, PI. I, (1), fig. 

 1_6). The author found the larva in exsuding sap on an ulcerated 

 stem of an elm in March and the following year at the beginning of 

 June; it pupated in the first days of August and after a week the 

 imago appeared. Schiner mentions (Verh. zool. bot. Gesell. Wien, VII, 

 1857, 446) that he bred the species from decaying poplars (I think 

 Schiner speaks of conopsoides, but it cannot be seen, as an asterisk 

 has been omitted). In Faun, Austr. Schiner says that the metamor- 

 phosis of several species is known, but he quotes only Dufour, and I 

 am not aware that the metamorphosis of any other species than 

 conopsoides is known. The pupa is mentioned by Vimmer (Casopis, 

 Soc. ent. Bohem. VIII, 1911) but this paper I have not seen. 



According to Dufour the larva is elongated oval, flat below, arched 

 above; the dermis is chagreened from small spines; the prothoracal 

 segment is covered with spines and warts; at the anterior end are as 

 usual the antenna-like organs, each ending with two cylindrical papillæ ; 

 near to the hind margin of the prothoracal segment is at each side 

 a not small anterior spiracular tubercle. At each side the segments 

 have three warts, one towards the dorsal side with five or six hairs and 

 two warts towards the ventral side, each with three spines; on the 

 thoracai segments are only two warts ; at the posterior end the warts 

 become longer filaments with more hairs or threads. The posterior 

 end has a rather long, cylindrical posterior spiracular process, more 

 than one third of the body in length; it has five or six stellately 

 arranged (branched?) threads at the apex. The length of the larva 

 is 10 — 12 mm, The pupa is grey and black variegated; it is similar 

 to the larva but narrower and more arched; the warts and fila- 

 ments at the sides are present only as small spines, longer at the 

 sides of the posterior part; also on the dorsal side of the segments 

 some spinules are visible (not mentioned for the larva but certainly 

 present in the usual arrangement). There are no anterior spiracular 

 tubes. The pupa is of the same length as the larva. 



The species of Cerioides are very characteristic and beautiful flies, 

 highly resembling species of Conops ; they are recorded to occur especi- 

 ally at ulcerated trees with flowing sap. 



