MARYLAND GEOLOGICAL SURVEY 173 



the intramedial region is about one-half its anterior width. 7 The frontal 

 or interantennal teeth are two, triangular, acute, with faint indications 

 of two others on their oblique inner margins (Plate XXIV, Fig. 1). The 

 median subfrontal spine is conical and strong. The inner supraorbital 

 tooth is broad and bilobed, the lobes obtuse, the outermost very promi- 

 nent. The adjoining fissure is closed except at the anterior extremity, 

 where there is a shallow V-shaped opening. The lateral teeth are con- 

 cave on both margins and acuminate. Lateral spine in males from three 

 to about four times the length of preceding tooth. 8 Inner suborbital tooth 

 acute. Penultimate segment of abdomen of male (Plate XXV, Pig. 1) 

 much constricted in its proximal half, widening at both extremities. 

 Terminal segment obtuse, lateral margins convex proximally, slightly 

 concave or straight distally. Appendages of first segment 9 (Plate XXVI, 

 Fig. 1) reaching nearly to or beyond the extremity of the abdomen, near 

 together for their proximal half, with only a slight outward curve; distal 

 portions widely divergent except at tips. The abdomen of the adult fe- 

 male (Plate XXVII, Fig. 1) is very broad, the margins of the last three 

 segments separately convex; terminal segment longer than wide. Costa? 

 of carpus and manus with depressed granules or often almost smooth to 

 the eye. 



Medium-sized specimens. — Carapace narrower than in adults ; granules 

 more distinct, especially on the anterior half. Frontal teeth less acute. 



7 The transverse dimensions of the intramedial region, or that division of 

 the gastric region posterior to the second granulate ridge, I have designated 

 as its width. Ordway does so under C. toxotes, but uses the opposite term 

 under G. ornatus. Thus the intramedial region of both he describes as long 

 and narrow, which is misleading, the two species being entirely different in 

 this respect. 



8 Measurements are made from the tips of the spine and tooth to the 

 inner end of the intervening sinus; thus the spine is measured on its anterior 

 margin, the tooth on its posterior margin. 



9 In both sexes of Gallineetes the first abdominal segment is almost entirely 

 concealed beneath the carapace; thus the abdomen in the male consists of five 

 segments, the third, fourth, and fifth normal segments being coalesced, the 

 first and second being furnished with appendages. In the female there are 

 seven segments, the second, third, fourth, and fifth with appendages. In 

 plates xxv and xxvii the first two segments are not shown. 



