THE INSECT FOOD OF YOUNG GROUSE 89 



species. Unfortunately, owing to broken weather, working with the net was 

 only possible on six days, otherwise the list would have been even L istsof 

 more representative. Most of the specimens were collected on the msects - 

 actual feeding grounds of the young Grouse, and the list is therefore 

 useful as showing the variety of diet possible during the first fortnight or 

 so of the chick's life. 



On a typical Grouse moor by far the greatest variety of insect-life is found 

 in the marshy ground around the sources of the streams. In every such place 

 the entomologist, by using the sweeping net, finds an abundance of specimens 

 and a fair variety of species. Diptera largely preponderate, but small Tineid 

 Moths, May-flies, Stone-flies, and Spiders are also plentiful. On the higher and 

 drier ground many other insects occur, including Crane-flies, Bees, and the 

 larger Lepidoptera, as well as a few others which must be regarded as of mere 

 casual occurrence, such as Syrphidce or Hover-flies, the Bomlws or Humble- 

 bee, etc. 



In Appendix E will be found a detailed list of the contents of 

 the crops and gizzards of forty - five chicks examined. The birds were 

 captured by hand and immediately killed by chloroform, dissected the 

 same day, and their crops and gizzards transferred to methylated spirit. 

 The contents of both crops and gizzards were afterwards examined, and 

 the fragments carefully compared with whole pinned insects obtained on the 

 same ground as the chicks. In many cases the remains were so crushed and 

 fragmentary that it was impossible to ascertain their nature, beyond the fact 

 that they were Coleopterous, Dipterous, etc. Where the generic and 

 specific names are both given, it may be assumed that the identification is 

 certain. 



The commonest insects in the crops are undoubtedly Diptera of the family 

 Limnobiidffi. Seventeen crops contained specimens that could be referred to 

 this family, and of these no fewer than fourteen contained the curious Insects 

 little species known as Molophilus ater. In one case (that ticketed ^cmiy " 1 " 

 Moor, No. 2-22) there were over one hundred specimens of this fly. eaten - 

 According to Dr Wilson's estimate this bird would be from eighteen to twenty 

 days old, and its crop was gorged with the remains of Molophilus ater, and 

 contained also two other Limnobiids, besides a few tips of heather. Other 

 crops from the same moor, belonging to chicks a week old or less, contained 

 fifty-six, fifty, thirty-four, and eleven examples respectively of the same fly. 



