61 



THE MOLE CRICKET— GRYLLOTALPA BORE ALTS. 

 By E. W. Dora.\, College Park, Md. 



In the Report for last year, page 87, Mr. James Fletcher had an interestino; article 

 on his "pet" mole cricket (Fig. 35). At his suggestion I send a few notes upon the 

 larval form of the same specie.?. 



On January 4 last, Mr. A. I. Hayward, connected with our State Experiment Sta- 

 tion, brought me five larvte of the mole cricket, which were found in rather a peculiar 

 situation. He had a number of men putting up ice. The ice had 

 been removed from a considerable space, when, wading around in the 

 water with tall rubber boots on, he found the young mole crickets 

 swimming around upon the water. It seems there was no connection 

 between the open space and the land ; besides, as the weather was 

 very cold, they could not live upon or near the surface of the ground. 



The only reasonable theory in regard to the matter is that they 

 were buried in the mud at the bottom of the pond, which is a tem- 

 porary one, having been flooded with water only a month or two. 

 The wading through the mud dislodged them, when they at once 

 came to the surface. However, there are some difficulties in the way 

 of accepting this hypothesis. For example : Could the crickets 

 exist beneath the water in the soft mud so near the surface for so 

 long a time ? West wood says in regard to the European mole 

 cricket, G. vulgaris, that the villose coating of the body and wings 

 appears to protect them from the water. Our species has a similar 

 coating of fine hairs ; but in the larvae especially it seems scarcely 

 sufficient to protect it from the efiects of the water in a prolonged 

 submersion. Besides, could it live so long entirely surrounded by 

 water, cut off from the air % They must have been in the thin mud 

 very near the water to have bean thus stirred out. Fig. 35. 



They seemed very little affected by the cold or their bath; in fact, they were as- 

 "lively as a cricket," and were apparently very much at home upon the water. 



The life history of our American species, G. horealis, seems not to have been studied 

 extensively. At any rate I have been unable to find figures or descriptions of the pre- 

 paratory stages. It is stated that G. vulgaris requir-es three years to come to maturity, 

 and horealis seems to b=i very slow in growth. When these specimens were taken they were 

 but little more than half an inch in length. They are at this time (March 15) about 

 .7 inches long. In two and a half months they have increased in length but little 

 over one-tenth of an inch, though they have been kept in a warm room and supplied 

 with plency of food, consisting chiefly of the roots of growing wheat, earthworms, etc. 

 As the female deposits her eggs in early spring, they are probably nine or ten months old 

 now. The mature insect is an inch and a half long, while these are but little more than a 

 third as long. Westwood says that vulgaris is inactive in winter. These have been 

 active at all times ; that is, not in any sense torpid, nor were they when taken. 



When I first secured them I put them in a jar of earth, and gave them no further 

 attention for several days. In the meantime one disappeared, and probably served to 

 satiate the appetite of the rest, as they are known to devour their own kind sometimes 

 when they can obtain no other food. 



Since then, in exhibiting another before my class, it was accidently injured and died. 

 I shall try to rear the remaining three to maturity, and figure the various stages. I can- 

 not say what stages they have already passed through. The larvae of vulgaris a.re white 

 before the first moult. These were dark velvety, and had moulted once or twice, I sup- 

 pose. They have not moulted since. 



I have written these notes in the hope of ciUing out other observations upon the 

 early stages of the insect. And I should be glad to know of any one who has studied or 

 figured the preparatory stages. 



