40 GRASSHOPPERS AND OTHER INJURIOUS INSECTS OF 1911 AND 1912. 



In 1911, Mr. Stoner, a field assistant, selected several specimens 

 of Mdanoplus bivittatus bearing abnormally numerous mites (26 

 to nearly 50 individually) and kept these under observation for a 

 period of two weeks. He reported that the hoppers appeared 

 normal in function and could observe no apparent injury due to the 

 mites. During the second week, however, he reported that the 

 mites on one of the hoppers were "drying up" or shrivelling. 



The Tern, so common about the prairie sloughs, aids the farmer 

 materially as these dry up toward the end of summer, by catching 

 countless grasshoppers. Mr. Somes was so impressed by this fact 

 in 1911 that he writes as follows: 



"The Black Tern is credited with destroying enormous numbers of hop- 

 pers; in fact, I have been told by two different farmers in widely separated 

 parts of the state that this bird had virtually saved their crops by i-educing 

 the grasshoppers to normal numbers. In both cases the conditions were simi- 

 lar — the farms were located in a marshy area and as the marshes dried in 

 summer the Terns turned to feeding on the grasshoppers and being present 

 in large numbers they usually were very effective." 



We also add here Mr. Somes' deduction from Mr. Zetek's notes 

 on Musciiia stabulcnis and HcUcobia lidices. 



"At Fergus Falls two flies were reared from Melanopli. Of these 

 Mnsciua stabnJaus, Fallen, is possibly a scavenger in habits rather than a true 

 parasite. It has been known from a wide variety of hosts, ranging from the 

 larvae of Aletia xyliixi (The Cotton-worm) and bees to fungi and even rotting 

 squash. In our studies however it was parasitic. The following taken from 

 Mr. Zetek's notes gives the general data as to this species. 'July 17th. At the 

 farm of Mr. Lomar, two miles west of Fergus Falls, I collected a number of 

 Melaiioplus bivittatus which contained dipterous lai"vae in the thoracic region. 

 They seem to be in the digestive tract. Placed in a tumbler cage. Several 

 larvae killed in hot water and preserved in alcohol. (Ac. No. 605.) Aug. 8, 

 10 A. M. Have examined the cage daily since the 17th ult. Adult flies ob- 

 sei'ved this A. M. These have emerged since August 7th, 8 P. M. Pinned 

 seven adults (Ac. No. 609) and placed in diy vial puparia of these as Ac. No. 

 610.' To go into more detail will say that the larvae mentioned in this obser- 

 vation was found on numerous occasions in Mekuiopnh bivittatus in numbers 

 varying from one to eight in the thoracic region as stated. The living larvje 

 were clustered close about the digestive canal in every case observed. Al- 

 though this species belongs to the Muscidae, as now limited, we think that it 

 must be parasitic although possibly also a scavenger in habits. 



Helicobia helices Toiviis. This Sarcophagid has previously been reared 

 from Luchnosterim, Pieris rapae, Leucauia, IMelaiwplns differeiitialis and 

 other hosts. In the case of this fly our studies would tend to lead to the 

 opinion that this is indeed a scavenger rather than a true parasite. (Zetek.) 

 Melanoplus bivittatus, adult, collected June 30, by Mr. Stoner at Ada in a 

 wire cage in a field of barley. It was placed in a cage for experiments with 

 mites. July 11 it was found dead and infested with larvje. July 12, trans- 

 ferred by Mr. Stoner from Ada to Fergus Falls. I placed it in a tumbler 

 cage. There are seemingly two kinds of larvae, — two specimens are large and 

 are probably Syrphids. One of these shows indications of pupation. The 

 other four larvae are longer (about 4 mm.) and flattened dorso-ventrally. 

 The jaws are well pronounced. None preserved as thei'e are too few larvae. 

 Aug. 8, 10 A. M., Cage has been examined daily and this A. M. found 4 files 

 in it. Pinned as No. 612. Exopuparia placed in a dry vial as No. 614." 



