235 



only ne<j^Jitive results. The author also records some iiiterestiug" facts 

 coiieerniu^' retardatiou of developnieut. On April l*r>, 1889, he received 

 a sack of barley sereeuiujis from the 1SS7 harvest, and out of 100 pu- 

 paria he found in 15 still living larv;e. These were shriveled, but u])on 

 being placed in damp sand they apparently entirely recovered, and on 

 May a perfect male insect issued. Others a]»]>eared from June 3 until 

 July U, some females being among those last appearing. From this (►!)- 

 servation it appears that the insect may rest two years in the puparivim. 

 This is confirmatory of what we hav(^ publivsbed on tlie subject and has 

 an important bearing upon the argument advanced by Wagner, Hagen, 

 and others, to the effect that the length of tbe journey would have pre- 

 cluded the introduction of the insect by the Hessian troops during 

 the Kevolutiouary War. The paper is illustrated l)y a handsome i)late 

 showing the larva and pui)a in different stages of growth and illustra- 

 ting the manner in which the larva turns beneath the leaf sheath. Mr. 

 Enock concludes his paper with a strong plea for the establishment of 

 a Government Bureau of Entomology, and pays Insect Life, as well 

 as the Division from which it emanates, some very high compliments 

 for which we beg to thank him. 



Bacteria normal to digestive Organs of Hemiptera.* — In this article Prof. 

 S. A. Forbes announces the interesting discovery that certain ca?cal 

 appendages of the small intestine which are always present in the 

 higher Heteroptera are invariably filled with bacteria which do not 

 occur in other portions of the body. These cseca were first noticed by 

 Leon Dufour, who called them ^'■cordons rah'ulei(.i\^' and vary in num- 

 ber, shape, and disposition. They are well furnished with tracheal 

 branches and connect freely with the interior of the intestine. Prof. 

 Forbes has found them in the Lyg.ieidai, Coreida^, Pentatomidie, and 

 Corimelicnidie, but failed to find them in the Capsida?, Xabidse, Eedu- 

 viidae, and Aradidte, and generalizes to the effect that they are found 

 in the higher Hetero])tera and are absent in the lower, while in those 

 intermediate in the scale they may be x)resent in one genus and 

 absent in another. The bacteria found belong to the species known as 

 Micrococcus insectornm. Where they were most abundant (as in the 

 case of dying Chinch Bugs) the epithelium of the ca'ca was completely 

 disorganized, only the basement membrane remaining. The structure 

 and arrangement of the ca*ca in several of the genera examined are 

 carefully described in this paper, but the author states that he has no 

 present desire to si)eculate concerning the meaning of the bacterial con- 

 tents of the organs, and offers this paper simply as a preliminary ac- 

 count of the several investigations upon which he is now engaged, and 



* Article I, Bulletin of the Illinois State Laboratory of Natural History, vol. iv., 

 pp. 1 to 6. 



