300 REPORT UNITED STATES ENTOMOLOGICAL COMMISSION. 



extremities are brought together and released almost simnltaneonsly. This kind of 

 molting, which is characteristic of our blister-beetles up to the pseudo-pupal state, is 

 exceptional among insects, the skin being ordinarily worked backward from the head. 

 The modification at this molt is slight. The mouth-parts and legs become rudimentary 

 and the body takes on more fully the clumsy aspect of the typical Lamellicorn larva, 

 for which reason I designate this as the Scarcibceidoid stage of the second larva. 



Another six or seven days elapse and the scarabseidoid skin is rent and shed with but 

 slight modification in the form and characters of the animal.^^ In this, the Ultimate 

 stage of the second larva (PI. IV, Fig. 5), the creature grows apace, its head being con- 

 stantly bathed in the rich j aices of the locust-eggs, which it now rapidly sucks or more 

 or less completely devours. [Upon disturbance the larva always emits from the mouth 

 a considerable amount of milky fluid.] The color is more yellowish than it was before, 

 and the power to stretch and travel on the venter on an even surface is still retained. 

 In another week it forsakes the remnants of the pabular mass, and, by burrowing a 

 short distance in the clear soil, avoids the deleterious decaying influences of these egg 

 remnants. [An examination of such egg-masses as have been gutted and deserted by 

 these larvse shows no trace of excrement, and indicates that the faeces are trifling 

 in quantity, and of a fluid nature. Fragments of the egg-shells are pushed up to the 

 top of the mass as fast as the larva devours their contents, and, together with an occa- 

 sional cast-off head, form the only rt j ectamenta. ] In the soil it forms a smooth cavity, 

 within which it lies stretched on one side, motionless and gradually contracting. The 

 skin separates and becomes loose at the end of the third or fourth day, when it splits 

 on the top of the head and thoracic joints and is worked toward ihe extremity, but 

 never fully shed. The mouth-parts and legs are now quite rudimentary and tuber- 

 culous, the soft skin rapidly becomes rigid and of a deeper yellow color, and we have 

 what has been called the semi-pupa (PL IV, Fig. 8). The term pseudo-pupa given it 

 by Fabre is more approx^riate, and I should prefer myself to call it the Coarctate Larva, 

 for it is nothing but a rigid and dormant larval stage, having its counterpart in the 

 well-known " flaxseed" stage of the Hessian-fly larva and in the so-called coarctate 

 pupa of the Diptera generally. A similar dormant but less rigid larval stage occurs 

 with many Tenthredinidaa in Hymenoptera, and in fact, tie summer dormancy of cer- 

 tain Lepidopterous larvse and the winter dormancy of others is analogous. We find 

 something similar, therefore, in all the Orders undergoing complete transformations, 

 but in no insects is the change so marked and exceptional cr the freeing of the subse- 

 quent larva from the coarctate larva so striking as in these Meloidas. The insect has 

 the power of remaining in this coarctate larval condition for a long period, and gener- 

 ally thus hibernates. 



In spring the coarctate larval skin is, in its turn, rent on the top of the head and 

 thorax, and there crawls out of it the Third Larva,^^ which differs in no respect from 

 the ultimate stage of the second larva already mentioned, except in the somewhat re- 

 duced size and greater whiteness. The coarctate skin, when deserted, retains its 

 original form almost intact. The third larva is rather active, and burrows about in 

 the ground ; but while there seems to be no reason why it should not feed, nourishment 

 is not at all essential, and all my specimens have, in the course of a few days, trans- 

 formed to the true pux)a without feeding. In the transformation to pupa (PL IV, Fig. 9) 

 the third larval skin is worked into a wrinkled mass behind, as is also the skin of the 

 true pupa when shed. The pupa state lasts but five or six days, and before the wings 

 of the imago are fully expanded, or the abdomen contracted, the general aspect of 

 Epicauta forcibly recalls the mature Henous. 



" None of the observers of 2Ieloe or Sitaris mection the two molts which the second larva undergoes, 

 tboush these doubtless occur in those genera as they do in Epicauta. Only by the raost careful watch- 

 ing from day to diy of a number of specimens have I been able to observe these molts ; fcr the exuviae 

 are genera-ly devoured as soon as they are cast, and this fact doubtless accounts for their not having 

 been observed in the two genera first mentioned. 



65 The coarctate larva is, properly speaking, the third, and that following it the fourth ; but just as I 

 have preferred to designate as special stages of the second larva the stages between the h'-st and 

 fourth molts, so I prefer to call the last Urva the third, to conform to the uomencltiture now generally 

 employed. 



