March, 1901.] Saiith : On Some Digger Bees. 39 



inches below the surface, where a loaded cartridge was found on a bed 

 of hard gravel. A heel extended from the end of the cast into this 

 gravel, and below it, almost four feet below the surface, another 

 loaded cartridge was found. To this species then, belongs the dis- 

 tinction of making the deepest digging of any species of the genus, 

 and also the boring of the greatest diameter. It is puzzling why this 

 should be so, but so it is. 



I have specimens taken at Newark and in Burlington County in 

 May, and a specimen dated Lahaway, June 20th. This is, therefore, 

 one of the later of the species, though A. hilaris I have from Laha- 

 way July 17th. 



So far I have six species of Andrena from Lahaway : A. hilaris 

 Sm., April 20-July 17th; A. vidua Sm., May and June; A. bicolor 

 Fabr. , June ; A. tiitda Robt., May and June; A. salicis Robt., with- 

 out date; A. viola Robt., April to June. 



Notes are here given on the digging habits of three of these, and 

 they are found to be essentially alike, though each has some little pe- 

 culiarities of its own that would probably show out more markedly on 

 closer observation and more frequent casting. 

 Halictus, sp. 



June 4th our attention was attracted by occasional small burrows, 

 not exceeding an eighth of an inch in diameter. The maker was a 

 small bee, determined by Mr. Ashmead as Halictus sp., and only two 

 or three examples were taken. 



The galleries drop down vertically about 15 inches, then a little 

 lateral runs off about an inch and a half, at right angles. At the end 

 of this is a drop of about half an inch and then a very pretty little cell, 

 carefully smoothed inside and soaked with saliva or some other se- 

 cretion. This turns black, the color penetrating quite deeply and 

 cementing the soil particles as far as it extends. At the bottom of 

 this cell is a very handsome ball of dry pollen, shaped like an apple 

 and quite regular. 



The desire to complete the history of Augochlora made it impos- 

 sible to devote further time to this species. 



There are, it will be noted when the history of Augochlora is writ- 

 ten, two types of storing diggers ; one which makes a paste with 

 honey and pollen stored in a thin membrane-like sac ; the other which 

 lines or hardens the inside of the cell and stores the pollen dry in a 

 loaf of definite form. I have little doubt that this difference in habit 



