48 NEW DJPLOPODJ OF THE GENUS OXTDESMUS— COOK. vol. xviii. 



Repugnatorial pores 11, dorsal on the outer slope of tlie iiitramarg- 

 iiial ridge of segineuts 5, 7, 9, 10, 12, 13, 15-19. Penultimate segment 

 exceeding- segment IS. Last segment broad, or very broad, tlie apex 

 more or less evidently emarginate; superior lateral tubercle usually 

 not large. 



Sterna witbout special structures. Male legs soiiieMiiat crassate. 

 Male genitalia flexed, and inserted under tbe edge of the aperture. 



Descripiion. — Body large, about six times as long as broad; cavity 

 nearly circular. Vertex prominent, rough; sulcus very deep. Antenn;B 

 scarcely clavate; third joint nearly as long as the second, or subequal; 

 joints in order of length G, 2, 3, 4=5, 1, 7. 



Mandibulary stipe with exposed surface divided by sutures into six 

 areas, two triangular, four trapezoidal. Masticatory plate lunate, 

 oblong, the surface crossed by eight to ten transverse ridges, alter- 

 nating with grooves. Dentate lamella with three to four broad, rounded 

 teeth. Pectinate lamelhe, six. 



Mentum triangular-cordate, slightly broader than long, broadly 

 emarginate posteriorly, anterior angle sharp or rounded. Cardo small, 

 pointed distad. 



Lingual lobes with one small cone concealed on the dorsal face; 

 median lobes with styliform processes long and simjile. 



First segment semi elliptical, with the lateral corners i)roduced and 

 somewhat recurved, much broader than the head, longer and somewhat 

 narrower than the second segment. 



Lateral carina' broad (one-half as wide as the body cavity), inserted 

 near the top of the body-cylinder; sharp and thin at tlie entire or 

 slightly sinuate edge, with a prominent, smooth and shining submar- 

 ginal ridge. Anterior carina^ laterally curved forward, the posterior 

 with corners produced candad; dorsal surface finely granular, divided 

 by furrows into three transverse rows of more or less evident quad- 

 rate areas, usually with one large, smooth granule in each. 



Below the carina' the segments are rough with conic warts ; a rounded 

 prominence just above the front pair of legs, larger in the male. 



Eepugnatorial pores opening dorsally on the outer slope of the sub- 

 marginal ridge of segments 5, 7, 9, 10, 12, 13, 15, IG, 17, 18, 19; pores sur- 

 rounded by a raised rim. 



Anterior subsegmeuts finely wrinkled longitudinally, sometimes very 

 obscurely. Supplementary margin long, membranous, very finely 

 striate longitudinally, not pectinate. 



Anal segment finely granular, posteriorly transversely wrinkled and 

 slightly decurved; the apex broad, rounded-truncate; on the margin 

 three pairs of setigerous punctations, two pairs located on tubercles; 

 the ui)per surface with two pairs and the under with one pair of setig- 

 erous punctations, more or less elevated. 



Anal valves with two setigerous tubercles, tlie upper placed on the 

 raised margin, the lower somewhat removed from it. 



