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leaves, carefully, however, as many as fifteen or twenty -'grubs" were 

 sometimes found on a single leaf. 



April 24 I collected a large number, which were placed in a jar in 

 order that their development might be more closed watched. Most of 

 these were still very small, only from 3 to 4 mm in length. When very 

 young they merely gnaw the under surface of the leaf, noticeable on the 

 upper side as small discolored spots, but as they increase in size they 

 eat entirely through both cuticles, making large roundish perforations. 



It is probable that there are but three larval molts, as, in the case of 

 even the smallest larva3 under observation, I was able to note but two. 

 and infer that one had been passed before they were brought in. 



The larger larva? entered the ground the 4th, 5th, and 6th of May, 

 penetrating to a depth of only from one-fourth to one-half an inch and 

 inclosing themselves in frail, nearly spherical, cocoons or cells of earth 

 cemented with a viscid secretion. Larvre, however, were found on 

 the spinach throughout the month of May. 



May 25 one of the beetles emerged, which proved to be Disonycha 

 collaris Fabr, ; and from this time until after the middle of June bred 

 specimens continued to come out. 



A package of specimens was sent to the Department in case it should 

 be considered desirable to have drawings made of the different stages 

 of development. Unfortunately this consignment did not reach Wash- 

 ington, and I did not learn of the failure until too late to replace it. 

 Specimens were, however, preserved in alcohol, which retain all the 

 important characters. 



No account of the immature stages of the insect or of its spinach- 

 feeding propensity is to be found in any work on economic entomology 

 to which I have access, and I think it has not heretofore been recog- 

 nized among the pests of the vegetable garden. I therefore subjoin 

 the following descriptions. 



Egg, not observed. 



Mature larva, from which the young differ only in size, 9 mm in length, 3 to 4 mm in 

 diameter; form subcylindrical, tapering slightly each way from middle segments, 

 which, both in resting and crawling, appears somewhat elevated or "hunched up." 

 Color a dirty, rather livid white, with a shiny, slightly viscid surface, each segment 

 produced with ten conical papillae — lateral ones largest — each of which terminates 

 in a minute bristle. Head about one-half the diameter of the thoracic segments, 

 oblique, circular, corneous, fulvous, paler in front, with dark brown mouthparts and 

 two dark brown, somewhat elevated, spots on each side. The posterior end of the 

 body terminates in a dark brown, corneous wing, most pronounced on the dorsal side, 

 fringed with bristles. This is always appressed to the leaf, and in moving the 'bris- 

 tles assist in propulsion. Legs concolorous with general surface, but with fulvous 

 or dingy brown annulations, the terminal joint being entirely of the dark color. 



Pupa, 8 mm in length, 3 in diameter across dorsum, with elytra and wings partly 

 extended as in other pupae of Balticinw ; the legs drawn up and folded close against 

 the body. Color pearly white in all its parts, acquiring a translucent gray tinge 

 before the last transformation. 



Beetle quite pale at first, gradually acquiring the dark metallic green of the elytra, 

 buff thorax, dark legs and under surface and other colorational characteristics of the 

 mature insect, 



