Doering: Lepyroxia quadrangularis. 557 



are more or lo?s telescoped, few details of structure can be made out 

 without first removing the legs. Its color is like that of the rest of 

 the body, and is uniform throughout with the exception of the 

 sutures, whicii are somewhat lighter in color, indicating their mem- 

 branous nature. The abdomen is A-ery wide at its base, but tapers 

 to a pointed apex, dui' to the fact that the segments decrease in 

 size from front to rear. Each segment overlaps the following one, 

 whicli produces a telescopic effect. The segments are divided into 

 three general regions — tergum, pleuron, and sternum. The tergum 

 occupies all the dorsal region, while the jileuron and sternum are to 

 be found on the ventral surface. 



The ventral, dorsal and lateral views of the male abdomen are 

 shown on plate LIX, figs. 1, 2 and 3. The first segment was diffi- 

 cult to find, owing to its irregularity of shape and its half-mem- 

 ])ranous structure. The tergum is partly membranous and partly 

 chitinized. although the chitin is very weak even where it is present. 

 Along its cephalic margin is a transverse, chitinous band, which 

 mesad is very narrow but which is broadly expanded laterad. This 

 anterior band is separated from a similar posterior, chitinous band 

 by a strip of membrane. The first tergum appears to be attached 

 to the postscutellum by a membrane. 



The pleuron (pi. LIX, fig. 2) of the first segment is greatly re- 

 duced and occupies a peculiar position on the abdomen. It is a 

 small, triangular, heavily chitinized plate lying on the laterocaudal 

 angles of the tergum. This is the only pleuron visible from the 

 dorsal view of the abdomen, but is easily recognized as such by the 

 distinct spiracle located near its upper margin. 



The sternum is also greatly modified. Its anterior margin is pro- 

 duced into a flaplike structure which bends forward on the re- 

 mainder of the segment, due to pressure from the thorax (dotted line, 

 pi. LIX, fig. 1). The lateral parts of the first sternum are mem- 

 branous and deeply depressed where the chitinous angles of the 

 thorax fit down against it. 



The tergum of the second segment is entirely chitinous, not ex- 

 tending across the entire dorsal surface of tlie alxlomen, but with 

 its lateral, rounded margins extending cephalad and bounded by 

 the cephalad-projecting corner of the thiixl tergum. 



The pleuron (pi. LIX, fig. 1) of the second segment is of the same 

 shape as the pleuron of the first, but is somewhat smaller. The 

 relation of the two can be seen from a lateral view (pi. LIX, fig. 3). 

 The two bases of the triangles adjoin each other, while the apices 



