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seem to be sufRcienlly promment to project beyond that of the fore 

 wings when closed. In Diyocanij)a the wings are very distinctly re- 

 versed and are very slightly covered with scales, being almost pellucid ; 

 in this they are thickly clothed. The socket and bristle are wanting, 

 and the thorax is not crested, which characters remove it from the 

 Notodontiadse : hence I concluded it must be an aberrant genus of the 

 Bombyciada3. A few days ago one of my pupils brought me a co- 

 coon exactly like that which had been sent me by Dr. Melsheimer, 

 and containing a living caterpillar which used it for a habitation. — 

 This brought to my recollection a remark made by Dr. M. in one of 

 his letters, that he had got what he supposed to be an Oiketicus, and 

 would send me a specimen, but when the insects were sent no name 

 was attached to them, and I did not suspect them to be his Oiketicus. 

 Though not indeed a species of Oiketicus, it is a Sacktriiger as the 

 Germans would call it, for it drags along its bag-like cocoon whenever 

 it moves from place to place. In the margin is a sketch of the co- 

 coon of the natural size, with the caterpillar stretching itself out, as it 

 is wont to do when looking around. The cocoon, for such it really 

 becomes at last, is made of two oval pieces of a leaf very strongly fas- 

 tened together at the edges, and forming an oblong, 

 ovate cavity, thickly lined with brown silk, and there 

 is a circular opening at each end just large enough for 

 the caterpillar to crawl out. The head of the cater- 

 pillar is black and roughly punctured ; on each side 

 of it, just behind the five ocelli, is a slender, flexible, 

 spatulate, black, antenniform process, without joints, 

 and incapable of motion. It has four palpi, two re- 

 tractile and concealed, and two long ones (maxillary) 

 partly retractile, three-jointed, and always kept in brisk 

 motion when the caterpillar emerges from its case. — 

 The first segment of the body is black and corneous, 

 as are the first three pairs of legs, which are conical 

 and about equal in size. The rest of the body is red- 

 dish, the spiracles black. The prologs, of the full 

 number probably (for I could not see the last pair), are 

 very short, with only the terminal coronet of hooks ex- 

 serted. The hinder extremity is obliquely truncated, 

 the truncated portion circular, and forming a flat, drab-coloured plate, 

 which exactly fits and closes the hinder orifice of the cocoon when the 

 larva has rciiied within it. The caterpillar was foimd on the oak, 

 the leaves of which it cats. It feeds mostly by night, and moors its 



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