96 TERTIARY INSECTS OF NORTH AMERICA. 



three times as long as the leg-claws, arranged as if to drag the Ijody back- 

 ward. The abdomen is faintly divided into four segments, often entirely 

 obscured. Of these the terminal usually appears shorter than the others, 

 which are subequal. 



These divisions of the body are all that appear to have belonged to the 

 animal; and it is the most remarkable fact in its organization that it cer- 

 tainly had no distinct chitinous head. This is the more surprising from the 

 clearness with which the thoracic segments are marked. All that one can 

 find preserved is what appears to be a ring of buccal plates terminating 

 anteriorly the alimentary canal, and which was evidently capable of being 

 thrust forward a long distance beyond the body. If it were not for the 

 unusual preservation of the alimentary canal we should be forced to con- 

 sider the head as lost from all the specimens, notwithstanding the nearly 

 perfect preservation of the other parts ; but in several s-pecimens the ali- 

 mentary tul)e can be traced with ease half th.ough the body, terminating 

 in front in these more or less clearly preserved chitinous plates, arranged to 

 form a circle a little smaller than the coxal cavities. What is most remark- 

 able is the extension of this alimentary tube and accompanying buccal plates 

 like a ])roboseis far beyond the limits of the body; sometimes forward 

 (apparently through the anterior notch) to a distance in front of the first 

 segment equal to half the length of tlie latter ; more often directed down- 

 ward as well as outward, perhaps between the front legs, and occasionally 

 extending beyond the body to nearh' or quite the entire length of the same. 

 It seems to leave its direct course within the body at about the middle of 

 the firs't thoracic segment, directly in front of which position the buccal 

 plates appear in one or two specimens, apparently in the position of repose. 

 The various positions in which these buccal plates are found outside the 

 body, both -when their connection with the tube is traceable and when it is 

 obscure or fails, shows how perfectly movable a proboscis the creature pos- 

 sessed. The external parts of the head, then, may be said to have been 

 probably composed entirely of a flexible, extensible membrane capable of 

 protrusion as a fleshy proboscis, separated by no line of demarkation from 

 the first thoracic segment, and bearing as a2:)pendages only a series of buccal 

 plates for mouth-parts, and beyond this nothing — neither cranium, eyes, 

 antennae, nor palpi. In the absence of eyes, one would natiu'ally look for 

 the development of tactile organs of some sort; but nothing of the kind is 



