Some Studies of the Development of Lixus concavus, Say, 

 and L. macer, Leconle. 



By F. M. Wkbster. 



Concernino; the hal)its and transformations of the twenty-five species 

 of the genus Z/a-«5, inliabiting North America, North of Mexico, very 

 little appears to have been learned ; the hmited information we possess 

 relating exclusively to but three species. 



From the fact that adults o[ Lixus rubellus, Rand, have, on two oc- 

 casions, been observed in considerable numbers clinging to the blossoms 

 anil leaves of an aquatic p'ant, Pulvjs^onuin amphibium, this insect is sus- 

 pected of infesting that plant, the theory being strengthened somewhat by 

 the fact thit Z. parapleclicus, an European species, breeds in the stems of 

 .S'/«/«, or Water Parsnip. (Rep't Com. Agr., 1870, p. 71.) The larva:? 

 of another European s[)ecies, L. angusta/us, is said to mine in the stalks 

 of beans. 



Lixus pivciis, a native of California, is said by Prof Riley to form 

 galls in the stems of J;«^/<;z;zc,^?'i?/'. ( Proc. Ent. Soc. Wash., Vol. I, p. 2,2)) 



A single short notice, printed in 1866, by Mr. Townend Glover, 

 contains all the published information we have respectmg the life-history 

 o^ concavus. Mr. Glover states that he observed the female beede '"bur" 

 rowing into the foot-stalks of rhubarb, or pie-plant, and there depositing 

 a single egg in each hole." The ol)server failed to rear the young, how- 

 ever, as the htter died in a few davs, as soon as the stalks became with- 

 ered. (Rep't Com. Agr., 1865, p. 90.) 



Of the early stages of ;/W(:6?/", we likewise have but little published 

 information. Prof Riley reared it in 1872 from Chenopodium hybridum, 

 but the girdling habit of the larvai was not observed by him. (Loc. Cit. ) 

 Mr, D. W. Coquillett, in a short article published in 18S3, (Can. Ent., 

 Vol. XV, p. 113), states that on July 13th, i88r, near Wood>tock, Mc- 

 Heary Countv, Illinois, he observed a fe iiale of this species busily engag- 

 e 1 in giawing holes in the stems of a green Helianfhus grosseserratus, or 

 Wild San-flower. There were several holes in the stem, and in each he 

 found, one or two ej[g-;, of an elliptic ovoid form, polished, pale yellow, 

 an 1 measuring about two and one-fourth mm. in length. In the stems 

 of other similar weeds growinj; near by, he found several recently hatched 

 larvae. Stems of the sime species of weed were examined during the 

 Summer, and larvje in different stages of their growth were observed- 

 Sometimes two or three in the sime plant. Late in (Jctober, pieces of 

 these stems, from one and a half to three feet long, were found lying about 

 on the ground, evidently having been gnawed off from within, excepting 



