AN ISLAND SETTLEMENT. 71 



it up with, loose sand and usually, also, with a little flat stone, 

 to prevent parasites from entering. The cell measures one 

 cubic inch, the entrance tunnel being one and one-half centime- 

 ters long, and arcuate. A cell contains four or five fresh flies 

 (Lucilia, Eristalis, etc.), and torn off wings, sucked out thor- 

 aces, and in the middle of these, a big flat larva. 



When the larva is hatched the mother brings more and 

 more flies, the flies being larger and larger as it grows. This 

 adjustment of the size of the fly to the growth of the larva has 

 also been noted by Fabre. 



"Wesenberg says that fifty Bembecids will nest on a spot as 

 big as a room during a period of three months. The time re- 

 quired for the development of the larva is two weeks, this 

 giving five or six young ones for the season. He queries, 

 "Does each female have more than one nest? and if so how can 

 she remember them?" To determine this point we marked six 

 wasps by touching them with differently colored paints, putting 

 near their nests pebbles painted to correspond with the owners, 

 and then watched them closely for three hours. During this 

 time the red wasp returned regularly to the red nest, the blue 

 to the blue, and so on. They were watched for an hour and a 

 half on the following day with the same result. So that it 

 seems quite certain that spinolae has only one nest at a time. 

 To feed two larvae at once, with interlopers thrown in, would 

 be a heavier task than the most determined industry could ac- 

 complish. 



"Wesenberg states that all the digger-wasps with the exception 

 of Benibex furnish the food for their young once for all, either 

 first laying the egg and then putting in food, or first filling the 

 cell with food and then laying the egg upon it, and covering the 

 whole without again visiting the cell or seeing their larva. We 

 know now that this too general a statement. At least one spe- 

 cies of Lyroda (subita) brings food to its young from day to 

 day. We have seen that Mwiedula does the same. In West- 

 wood's "Classification" we find that the same habit has been 



