TENTH REPORT OF THE STATE ENTOMOLOGIST 403 



mens of Pliora agarici were examined. In many cases the two wings were 

 compared; in every case where the tip of the second heavy vein was apparent, 

 these structures were found constant in number and position. It requires a 

 mounted preparation and a one-fourth objective to bring them out clearly. 

 Though occurring on the under side of the wing, in this species the veins are 

 sufficiently transparent so tliat the pores may be seen from the upper side. 



Subsequent study has shown that similar pores occur in the genus Sciara. 

 They are found along the rudimentary sub- 

 costal vein and are much smaller than in ^ " ^ ° ° ° ""^ q q '' 

 Phora. In S. coprophila there are 10 pores 

 along this vein — an outer group of three, of 

 wliich the antepenult is on the inner margin 

 of the vein; the inner seven are nearly 



equidistant (figure 7a). In S. caldaria there Fia. 7. — Diagram showing pores in 

 , , ~ veins of Sciara: a, S. coprophila ; 



are but seven pores — an outer group of 6, s. caitajia ,• s, outline of sub- 

 three, with the antepenult as in S. coprophila; costa; r, fore u^argin of radius. 



the inner four equidistant (figure 7b), 



Reference may be made, in connection with the above, to a paper 

 published in 1889 in the Transactions of the Royal Society of South 

 Africa, by the late Ezra P, Crawford, entitled " Notes on Certain 

 Pores in the Veins of Some Diptera," and illustrated by several fig- 

 ures. Mr, Crawford found them to " number from five to eight, when 

 present, and their number and position are constant in each species," 



It is thought that they may be homologous with what Jurine, in 

 JSFouv. Meth. class. Jlymeno^?. et Dipt., 1807, named "bulla?," as 

 observed by him on the wings of certain Hymenoptera. 



Infestation of Mushrooms by Phora, 

 Mr, Falconer ha-? kindly sent, in response to request, the following 

 observations on the occurrence of the Phora larvoe: "They make their 

 appearance in early April, but do not iocrease to such an extent as to 

 completely ruin the crop until the end of April or the first part of May. 

 In outdoor mushrooms they are to be found from May into October,. 

 From August onward they are more numerous in wild mushrooms than 

 at any time in cultivated ones, and they are apparently larger [but 

 slightly so, judging from indication given of comparative sizes], but 

 this may possibly be accounted for by a better food supply. In some 



NoTB.— The following information relating to Phora infestation of mushrooms has been kindly 

 communicated to me by Mr. Howard, of the Division of Entomology, at Washington, in reply to 

 an inquiry made: " We have reared Phora niinicta ia considerable numbsrs from mushrooms 

 received from Geo. Balderston, Colora, Md.: and in Europe, Mr. Coquillett informsme, Scholtz 

 has reared Phora lutea VIeig. and Phora flava Fall, from an agaricus (Schiner, Fauna Austriaca 

 Diptera, II, 1861, p. 34}). Leon Dufour reared P. nigra Meig. from Agaricus prunulus Fries 

 (1. c.,3J5), and Letzoer reared P. pumila Meig. from an agaricus (.1- c., 345). Phora bovistoe- 

 Gimmerth. was bred from Lycoperdon bovista (1. c, 316). 



