214 



THE GUIDE TO NATURE 



he be tempted to stop and enquire into 

 the life of these very small members of 

 the animal world and he will truly find 

 that they are rightfully named "Wes- 

 tern Harvesting Ants." 



(Dr. McCook calls them the accident 

 .ants.— E.F.B.) 



The Vigilance of a Digger Wasp. 



BY S. P. AARON, SECANE, PA. 



During the past summer I ran across 

 an old acquaintance, the big digger 

 wasp with the golden thorax. I have 

 been quite unable to determine the 



GOLDEN BACK WASP ATTACKING A SMALL 

 TRESPASSING BUMBLE BEE. 



specific name of this was]). It is a fine, 

 large species and very handsome. The 

 female is as long in body as the largest, 

 long-waisted Ammophila and as heavy 

 as a paper nest hornet, with an abdo- 

 men lacking the long petiole. I do 

 not know the male, although the spe- 

 cies is not uncommon in the South. It 

 is most closely allied to Pompilius and 

 Pepsis. Almost as large as the sand- 

 hill hornet, (Sphecius speciosus) and 

 even more striking in appearance it 

 seems strange that her biography ami 

 picture are not given in the books, for 

 such is the case. So we shall call her 

 the golden backed digger and trust that 

 students may know or discover her 

 name, possibly among the rarities. 



The digging habit of the golden back 

 is not unlike that of the Western tor- 

 nado wasp (Pompilus quinquenotatu's) 

 of which the Peckhams wrote so fully 

 and interestingly. She goes at her work 

 like a sizable whirlwind, throwing the 

 sand and gravel behind her in almost a 

 steady stream, enough to make one's 

 finger nails ache in sympathy, and it is 

 small wonder that her claws do not 

 wear out long before the large hole, 

 easily three-fourths of an inch in di- 

 ameter, is completed. It was in the 



sandy stretches of Southern New Jer- 

 sey that I watched her at work, within 

 a spot more than a yard in extent and bare 

 of vegetation except a few dwarf daisy 

 fieabane plants. When the burrow was 

 completed and she had entered it and 

 backed out more than a dozen times 

 without carrying a mite of dirt she 

 made a bee-line for some chosen hunt- 

 ing ground and in a few minutes re- 

 turned carrying something in her 

 strong jaws, something not large ana 

 that had legs drawn up closely in 

 death, but try as I would I was not 

 able to ascertain the nature of this cap- 

 ture, although I half believe it was a 

 spider. I had hoped something better 

 of her than this; a creature of such 

 furious energy and formidable propor- 

 tions should have captured something 

 like a powerful katydid, a giant horse- 

 ilv, a big hairy-legged lycosid spider 

 or at least shown herself something of 

 a St. Georgiana and overcome a spiny 

 dragon-like caterpillar whereon to feed 

 her baby wasps. However, she did not 

 lack courage as events proved. After 

 having made this first capture, which 

 may have been a mere tidbit for her 

 offspring, she rested awhile and care- 

 fully groomed herself, passing her legs 

 over the entire surface of wings and 

 bodv and comically cocking her head at 

 all angles during the operation of clean- 

 ins" her antennae. Then she began a 

 careful inspection of the immediate 

 premises within two or three feet of 

 her digging and examined ever) 7 bit of 

 gravel, every plant stalk and every 

 inequality of ground, going through 

 this undertaking with the utmost dis- 

 patch and hurrying back to the hole 

 every few seconds, using her wings 

 in part to add speed to her long legs. 

 Now and then she dived into the bur- 

 row and backed out again, sometimes 

 two or three times in quick succession 

 as if quite undecided that everything 

 was all right. The motive for all this 

 is what? Evidently Nature's evolu- 

 tionary method of teaching her race to 

 spy out and guard against the per- 

 sistent and numerous parasitic enemies, 

 such as Chrysis, Chalcis, Trypoxilon, 

 species of Bombex and perhaps Ich- 

 neumon and Braconid flies that will 

 seek to enter the nest during her ab- 

 sence and deposit an egg therein that 

 will hatch before her own and destroy 

 the maggot-like baby golden backs. 



