scuODEfl.J CANADIAN FOSSIL INSECTS. 63 



as distinct from Eoscorpius. Regarding the possible position and arrange- 

 ment of the lateral eyes, remarks will be found under the species. 



Mazouia acadica. 



PL v., tigs. 5, G (also figs. 8, 9 ? ). 



The species here referred to Mazonia and regarded as distinct from 

 M. woodiana irom the Carboniferous deposits of Mazon Creek, 111., is 

 primarily founded upon a single specimen and its reverse shown in figs. 5 

 and 6. These show the whole of the dorsal surface of the cephalothorax 

 (fig. 5) and its reverse (fig. 6), together with the basal segment of the 

 abdomen and part of the segment behind it. The cephalothorax is shown 

 to have had somewhat the shape of a horse's hoof, well arched anteriorly, 

 broadest in the middle of the apical half, narrowing very gently and 

 regularly to the abdomen which is of equal width with its base ; it is a 

 little longer than broad, tumid centrally but depressed broadly around the 

 sides, very strongly and abruptly elevated anteriorly behind the marginate 

 border and at the broadest portion, forming a slender transverse semi- 

 lunate prominence upon which the eyes (here abraded) are seated. On 

 the lateral margins, along the middle of the depressed portion and running 

 backward from opposite the ocellar prominence, is a regular series of about 

 half a dozen minute, subequidistant, subconical, and apparently crateriform 

 verrucosities, which the condition of the specimen permits to be seen on 

 only one side. If, as seems probable, these are the lateral eyes, their 

 number, position, and arrangement show that this scoi'pion cannot be 

 placed in either Eoscorpius or Cyclophthalmus, and renders our conclusion 

 that Mazonia may be retained the more justifiable. Behind the median 

 ocellar prominence and leading from the lunar horns of the same, there is 

 on either side an obscure ridge running parallel to the sides and, next the 

 posterior border of the cephalothorax, slightly elevated into a broad boss. 

 The first abdominal segment shows just behind these elevations a pair of 

 strongly elevated, subconical prominences only less raised than the ocellar 

 prominence, and from which run, backward and inward, converging on 

 the posterior part of the second abdominal segment, a pair of low ridges. 

 Wherever the surface structure can be clearly seen, it appears to be 

 smooth and light coloured, excepting for tolerably regularly scattered dark 

 circular pustules, in some places apparently slightly elevated or roughened 

 which are separated from each other by their own diameter or a little 

 more, and which have a diameter of from one-half to one-third that of the 

 supposed lateral ocelli. 



Length of cephalothorax, 8"""; its greatest width, 7'25""" ; width at 

 base, 6-75'""'. 



