238 APPENDIX F. ARACHNIDIANS. 



The upper surface of the cephalothorax and abdomen is covered with 

 minute granules extending over the palpi, being particularly dense on 

 the three first articles, and over the three first joints of the thoracic 

 appendages also. Minute impunctures are seen upon the remaining 

 articles and joints, and also scattered upon the inferior surface of the 

 appendages and body. Minute setae are scattered over the appendages 

 of the cephalothorax and abdomen, more densely towards their extremi- 

 ties. 



The color is uniform blackish brown above, and deep chestnut beneath. 



One specimen of this animal was collected. 



Plate XVII, fig. 1, represents, seen from above, Thelyphonus excubitor 

 the size of life. 



Fig. 2 gives the position, number, and relative size of the ocelli. 



Fig. 3 is a front view, exhibiting in the centre the chelicerse and the 

 three first articles (a, b, c) of the palpi. 



Fig. 4 represents the anterior portion of the cephalothorax from 

 below : a, first article, b, second article, and c, third article of the palpi ; 

 and d, anterior pair of feet. 



III. SCORPIONID^E. 



Although the collections made in the valley of Red river contained 

 no specimen of this group of arachnides, we have brought them here 

 to notice, satisfied as we are that they exist in that locality. 



Scorpions are found in the southern Atlantic States, all along the 

 Gulf of Mexico, through Texas and New Mexico to California, and 

 through Louisiana to Arkansas. 



1. Scorpio (Telegonus) boreus, Girard. 



Zoology, PI. XVII, figs. 5-7. 



Spec. char. — Body greenish yellow ; thoracic and caudal appendages 

 yellowish. Lateral ocelli in close contiguity; posterior one the smallest. 

 Median ocelli situated on the sides of an elongated and black elevation. 

 Chelicerge terminated by a serrated claw. Palpi robust, shorter than 

 the body. Caudal* appendage as long as the body, the spine excepted. 

 Abdominal comb with eighteen laminae. 



Description. — The general form of the body is fusiform, anteriorly 

 and posteriorly tapering. The cephalothorax proper is subquadrilateral. 



