6 PROCEEDINGS OF THE ACADEMY OF 



Descriptions of New Species of NORTH AMERICAN POLYDESMID.E. 

 BY DR. H. C. WOOD, JR. 

 Genus POLYDESMUS. 

 Subgenus FONTARIA. 



P. TRIMACULATDS. 



P. saturate rubro-brnnneus ; scutis postice fulvo trimaculatis, corrugatis ; 

 antennis ultirais pilosis; pedibus dilute fulvis ; appendicibus genitalibus mas- 

 culis niaximis, crassibus, ultimis obtuse rotuudatis, spina terruinali gracilliraa, 

 enormiter convoluta. 



The color of tbis species is a dark reddish brown. Each scutum has on the 

 posterior portion of its lateral lamina a bright yellow or orange spot, and a 

 blotch of the same tint on the median portion of its posterior border. Occa- 

 sionally this is so prolonged as almost to give the idea of a continuous trans- 

 verse band. The first scutum has two central markings, situated the one on 

 its anterior, and the other on its posterior border. These are so shaped and 

 joined together as to suggest the idea of an hour-glass. The anal scutum is 

 triangular and somewhat elongate. It is yellow, but has a dark spot on each 

 side, and its truncate apex is tipped with brown. The head is chestnut brown. 

 Its vertex is deeply canaliculate, and its inferior lip distinctly emarginate, and 

 fringed with hairs. The antennae are light brown, slender, and not at all cla- 

 vate. The feet are light yellow, with their distal portion somewhat pilose and 

 occasionally tipped with brown. The male genital appendages are very large 

 and robust. Their terminal spine is simple, long, slender, and irregularly bent 

 upon itself. They are also furnished with a small nearly straight spinule, 

 placed proximally as to the terminal. The female genitals are very short, 

 thick and bulbous. On one side of each there is an opening, with two pro- 

 jecting plates separated from one another by a linear orifice. I have seen a 

 male and female, which were collected by Mr. E. D. Cope in Susquehanna Co., 

 Pennsylvania. They are about two inches long. 



P. CORRUGATUS. 



P. atro-castaneus, scutis fulvo postice marginatis ; laminis lateralibus fulvis, 

 latissimis, angulis anticis rotundatis, posticis modice acutis : scuto anale tri- 

 angulare, elongato, postico fulvo, apice truncato; appendicibus genitalibus 

 masculis maxirnis, spinulo laterale robusto subbreve vix curvato armatis ; 

 spina terminale maxima, robusta, compressa, tortuosa, spinulo basale armata. 



The color of the perfect animal is a chestnut black, rarely reddish chestnut, 

 with a moderately broad margin of fulvous [in alcoholic specimens] on each 

 scutum. This band may be red during life. The scuta; beautifully po- 

 lished to the naked eye, the microscope shows to be obsoletely wrinkled. 

 Very many of these wrinkles are longitudinal. The head is of the same color 

 as the body ; medianly it is distinctly sulcate ; inferiorly it is broadly and 

 rather deeply emarginate. The scutal side plates are fulvous above and be- 

 low. Their anterior angles are rounded, their posterior more or less acute, and 

 in the hinder ones prolonged. The under surface of the body is of a light 

 yellow. The male genital appendages are very large and robust. They have 

 a short, slightly crooked spinule attached and lying close to their side. The 

 terminal spine is irregularly spiral, and has near its base a curved spinule. At 

 the point of its origin is a tuft of bristly hairs. Each female genital appen- 

 dage is chiefly composed of a short, almost globular, process, in one side of 

 which there exists a large opening. This process is scarcely at all pilose. 

 Through the side opening projects a pair of large, thick plates, fitting together 

 somewhat in the manner of bivalve shells. These nearly equal in height 

 the main process. The spine on the second joint of the feet is robust, 

 but acute. The whole animal is about one and a half inches in length. 



[Jan. 



