76 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



The contents of the nest were placed in a breeding cell which 

 was buried an inch below the surface of the sand in the garden. 

 On the morning of August 2 the egg had not hatched but the 

 caterpillars by spasmodic movements had changed their position 

 in the cell and most of them had passed faeces. They responded 

 readily when pricked with the point of the forceps. On the 

 morning of the third the egg had hatched and the young larva 

 was feeding upon the caterpillar to which the egg was attached, 

 pursuing a ctiurse quite similar to that followed by P. molacei- 

 pennis. On the morning of the fifth the first caterpillar was 

 almost completely consumed and the remaining ones responded 

 but feebly to stimulation. On the sixth the larva was devouring 

 the second caterpillar having its head and thoracic segments 

 thrust within the body of the caterpillar. On the morning of 

 the eighth it had devoured all the caterpillars and was beginning 

 the construction of its cocoon, which was completed on the ninth. 



The cocoon of this species is yellowish and semitransparent 

 whereas that of P. violaceipennis is almost black and opaque. 

 The adult of the latter emerged from the cocoon at the end of 

 about one month; the former has gone through the winter in the 

 cocoon. Sphex digs her nest and then searches for caterpillars 

 with which to provision it; Psamophila captures her caterpillar 

 and then digs a nest to put it in. Both bring the sand out of 

 the nest holding it with the front legs and mandibles. Psamophila 

 always backs away from the entrance of the nest with her load 

 of sand which she drops and walks over in reentering the nest. 

 Not so with Sphex; after backing out o r the nest with her load of 

 sand she turns round and carries the sand forward for some 

 distance from the nest and usually throws it in a neat pile. One 

 individual, however, after backing out of the nest flew up into 

 the air with each load of sand and scattered it in all directions. 



EXPLANATION OF PLATE. 



Fig. 1, Psamophila violaceipennis (Lep.) with caterpillar at entrance to 



nest. X ?. 



Fig. 2, caterpillar with egg of P. violaceipennis (Lep) in place. Natural 

 size. Egg deposited July 20. 



Fig. 3, larva from egg in Fig. 2, natural size. July 23. 



Fig. 4, larva from egg in Fig. 2, natural size. July 25. 



Fig. 5, larva from egg in Fig. 2, natural size. July 26. 



Fig. 6, cocoon formed by larva in Fig. 5, natural size. 



Fig. 7, egg of P. violaceipennis (Lep.) in place, natural size. 



Fig. 8, content of nest of Sphex urnaria (Dahlb.) in breeding cell, natu- 

 ral size. 



Fig. 9, Oxybelus 4-notatus Say at entrance of nest holding fly impaled 

 on her sting. X 2 



