March 1S92.J 



PSYCHE. 



233 



corn field. Six days after the bugs com- 

 menced travelling to the corn, the bugs 

 covered three feet of every stalk about ten 

 rods into the field. On the seventh day I 

 noticed there were not so many bugs on the 

 stalks. I then noticed that the bugs got less 

 in numbers every day until the tenth day 

 when I could scarcely find a bug on the 

 stalks. As the bugs were not more than 

 half grown, it seemed to me a strange act 

 that they left the corn entirely without kill- 

 ing it. 



I wondered what became of the bugs and 

 T turned over some lumps of dirt and out 

 flowed piles of dead bugs and live ones also. 

 By taking close notice I found that the bugs 

 had not left the field but had crawled down 

 in the dirt to die. Half of the bugs were at 

 that time dead. In a few days there came a 

 heavy rain which baked the ground. I have 

 not seen a bug there since." 



In making their reports as to the 

 benefit received from the use of the in- 

 fection, 495 of the 1050 successful ex- 

 perimenters gave their own estimates of 

 the number of bushels of grain saved by 

 the experiment. The sum of these es- 

 timates amounts in cash value to $89, 

 1 76-65 or an average of $180.00 for each 

 farmer. It is fair to presume that this 

 average may be safely applied to the re- 

 mainder of the 1050 successful experi- 

 ments. This gives an aggregate saving 

 of $189,000. This amount saved by the 

 farmers means additional profit for the 

 railroads and the millers, so that $200, 

 000 is a very conservative estimate of 

 the actual value of the experiments in 

 1891. 



CONCERNING THE -'BLOOD-TISSUE OF THE INSECTA.— II. 



BY WILLIAM MORTON WHEELER, WORCESTER, MASS. 



Among the Pterygota oenocytes are 

 of very general, perhaps universal oc- 

 currence. Wielowiejski found them in 

 Rhynchota, Aphaniptera, Coleoptera, 

 Lepidoptera, Hymenoptera and Diptera. 

 They had previously been noticed by 

 Graber in Orthoptera, Coleoptera and 

 Trichoptera. I have found them in a 

 number of orders in which they have 

 not hitherto been observed and here 

 subjoin a brief account of my observa- 

 tions together with a few notes on oeno- 

 cytes in some of the orders in which 

 thev have been studied by others. 



Orthoptera. The oenocytes of 

 Blatta and Xiphidium are very similar 

 and may be regarded as typical for this- 

 order. Arising, as above described, by 

 immigration from the ectoderm just 

 caudad to the abdominal stigmata, they 

 remain at their place of origin through-, 

 out embryonic life, but later some of the 

 anterior cells wander into the thoracic 

 cavity. In the adult the metameric ar- 

 rangement seems to be lost and the 

 oenocytes lie irregularly scattered along 

 the pleural and sternal walls. The 

 separate elements never show any ten- 



