SPHECIA APIFORMIS. 123 



SPHECIA AP1F0EMIS. 



Plate XXVII, fig. 1. 



The only date which Mr. Buckler has for this species 

 is February 25th, 1861, but as he also records that the 

 larva was taken out of its cocoon, the fact of the cocoon 

 being complete at this time of the year is established. 

 I have never found this species at large in any stage, 

 but have had cocoons given to me at various times. 



In 1886, March 8th, Mr. W. H. B. Fletcher sent me 

 a dozen cocoons, some of which I opened in order to 

 describe the larvae within ; the opening was effected 

 by cutting a slit through the whole length of one side, 

 and when I had done with each larva I replaced it in 

 its cocoon, the shape of which had not been altered, 

 and by the next day I found in each case the slit had 

 been spun together, and after another day or so it was 

 hard to distinguish the cocoons thus operated on from 

 those that had not been interfered with. Mr. Fletcher 

 and Mr. F. D. Wheeler inform me that the larva bores 

 in the bark and wood of Populus nigra, a few inches 

 above the soil and also below it, and its gallery is 

 driven not only into the trunk of the tree, but also 

 through the main roots, sometimes running to a con- 

 siderable distance from the trunk ; from the varying 

 size of the larvae found in the same tree they conclude 

 that the larval stage lasts for two if not three years. 

 When the larva has ceased feeding it constructs its 

 cocoon in its gallery near its exit, or sometimes in the 

 soil near the tree, becomes a pupa in May or June, and 

 the moth emerges in June and July ; some of those I 

 had this season were bred during the first week of 

 June. 



The cocoon is cylindrical, with rounded ends, from 

 25 to 35 mm. in length, and about 12 to 18 mm. in 

 width, tough in texture, being formed internally of stiff 

 silk, and coated externally with raspings of wood, but 

 its substance is not much more than 1 mm. in thick- 



