15 



In June, 1880, Mr. J. K. P. Vfallace, of Andersonville, Tenn., sent 

 to Dr. C. V. Kiley a number of wheat straws containing larvae, with 

 the complaint that nearly every stalk or straw was affected by them, 

 and, as a consequence, the straw was inclined to fall before the grain 

 had fully ripened. Mr. J. G. Barlow, of Cadet, Mo., about this time 

 also complained of a similar trouble in his neighborhood, in some cases 

 resulting- in nearh" a total loss of the crop. In the winter of 1881-82, 

 Dr. Riley was able to rear some 30 adults from these infested straws, 

 and, as he considered the species described bj^ Dr. Fitch only a variety 

 of the barley straw-worm {hosoma hordei Harris), he described the 

 adults obtained from these straws as Isosoma triticl Rile}^ Avhich 

 description was published in the Rural New Yorker March 4, 1882. 

 This was the situation and the condition of our knowledge of the 

 species at the time the writer was appointed a special agent of the 

 Division of Entomology, of which Dr. Rile}" was then chief, and 

 under his instructions began the stud}^ of these and other grain insects 

 in May, 1884. 



DISCOVERY OF THE SUMMER FORM. 



On May 8, 1884, in a field of wheat near Bloomington, 111., I found 

 hoHoina triticl Riley, as it was at that time known, in considerable 

 numbers, crawling over the 3'oung wheat plants, and on the 11th of 

 the same month watched a couple of females deposit their eggs in these 

 growing plants. On May 30, while examining plants from this same 

 wheat field, 3^oung Isosoma larvfe were found in the stems, and I also 

 found larvae in the stems in which I had observed the captured females 

 to oviposit May 11, but these last were much too large for Isomma 

 tritici. During the previous few da3's I had been getting from fields 

 of both wheat and rye in the same locality a much larger Isosoma, 

 possessing fully developed wings, and on May 29 a pupa, also too 

 large for I. triticl^ was found in the upper part of a dwarfed wheat 

 plant. In the light of more recent studies we now know thtit I had 

 three species under observation instead of one. The small individuals 

 found early in the month of April belonged to the spring form of this 

 species, and others were Isosoma webste7'i, while the larger individuals 

 swept from wheat and rye, later in the month of May, were some 

 of them the summer form [L graude), and others belonged to another 

 species, afterwards described as Isosoma captivuvn Howard. My field 

 of observation was at this time transferred from Bloomington, 111., to 

 Oxford, Ind. 



On June 6, in a field of wheat near Oxford, I observed female Iso- 

 somas, seemingly like those taken a few days before in the wheat and 

 rye fields near Bloomington, ovipositing in wheat plants, well up 

 towai'd the top of the stem, probably between the upper joint and the 

 one next below, although, on account of the head of the wheat having 

 not yet put forth, it seemed as though the ^gg was being placed in the 



