OF SILTJEIAN AND DEYOISTIAN. S 9 



divides the order Palseodictyoptera of Goldenberg, it seems plainly to fall in the second, 

 viz., Nenropteroidea. 



Size. — Length of the part preserved, 16 mm. ; probable length of the whole wing, 

 16| mm. ; width, 6 mm. 



Horizon and Locality. — This species was found by Mr. W. J. Wilson in the Plant-bed 

 No. 2, Cordaite Shales of the Lower Devonian series at Lancaster, N.B. ; the bed in which 

 the late Prof. 0. F. Hartt found Xenoneura antiqum-um. 



Aech^OSCOLEX cornexjs, u. gen. et sp. (Plate lY, fig. 11.) 



Body cylindrical, tapering behind the middle, and also at the three anterior segments. 

 Divided into three regions of head, thorax and abdomen. 



Head small, somewhat conical, appendages not known. 



Thorax of three joints, increasing in width backward, but decreasing in length. 

 Limbs tapering, the posterior pair as long as the thorax and larger and stronger than 

 those in front ; the two anterior pair slighter and jiartly concealed beneath the thorax 

 and head. 



Abdomen of eleven visible segments ; those at the anterior end are widest, those of 

 the middle longest. Five segments only are complete ; of these the basal segment has 

 an oblong scar near the posterior edge ; from this scar there extends across the other four 

 segments a very faintly marked band, pointed at the end, and having a duller surface 

 than the rest of the surface of the rings. 



The crust is chitenous, and its surface has a faint brownish tinge, and appears to be 

 minutely punctate. 



Size. — Length, 20 mm. ; width, 3 mm. Length of the head (as preserved), IJ mm. ; 

 width, IJ mm. Length of thorax, 5 mm. ; width, 3 mm. Length of abdomen, 14 mm. ; 

 width, 3 mm. 



Horizon and Locality. — From plant bed No. 2 in the Cordaite Shales, St. John, N.B. 

 Found by Mr. W. J. Wilson. 



There are some feattires in this organism which do not seem easy of interpretation ; 

 among these is an oblong scar, which is found on the fifth segment ; this is in the position 

 where a spiracle might occur, as is the case with the larva of several insects ; but these 

 spiracles are usually nearer the anterior edge of the segment than is the case with this 

 scar. If on the other hand we look upon this scar as marking the point of attachment of 

 a wing, we find no legs on this segment beneath the wing attachment marking it as a 

 part of the thorax ; and further there is no scar on the segment in front to mark the place 

 of an anterior wing. It may be remarked, however, that there is a dark band extending 

 backward from the scar on the fifth segment, along the side of the body, which may be 

 due to the impression of an embryo wing-sac ; this band does not show on the fifth or 

 anterior segment. 



This grub is the first example of the body of an insect recognized among the insect 

 remains found in the Devonian shales at St. John. That it is such and not a crustacean 

 seems clear from its general aspect and from the position and nature of the appendages. 

 The specimen is a little broken at the front, so that there may have been appendages to 



