ch.\mberlin: myriopoda of the Australian region. 141 



widening from base to near middle of length and then strongly convexly 

 rounded into a semicircle which is crenate, showing ten to twelve low crena- 

 tions bearing long setae. Valves strongly margined, coarsely roughened and 

 granular. Scale also granular, caudalh' weakly convex, with a large setigerous 

 tubercle at each lateral end of caudal border. 



Gonopods of male with telopodite distally flattened and strongly uncat«, 

 cur^dng dorsad and then caudad and di^^ding into two long prongs of which 

 the ectal is slender and acute, while the mesal one is proximally flat and blade- 

 like but distally di^■ided again into two slender acute prongs. 



Length, to near 55 mm.; width, 10.8 mm. 



384. Platyrrhacus (Diodontodesmus) mimus, sp. no\-. 



Type.— M. C. Z. 4,983. Par.a.types.— M. C. Z. 4,984. Solo- 

 mons: Fulakora (W. M. Mann). 



In the form of the gonopods much Uke P. verrucosn-f} (Pocock); 

 but the erect distal process is proportionately longer and more angu- 

 late proximally, while the cur^'ing transverse prong, though very 

 similar, takes its origin more dorsad and mesad than represented 

 for verrucosus. 



It is a notably smaller species than P. verrucosus, the male having a 

 ■wadth of only 5.2 mm. as against 9 mm. in the other species. The 

 dorsum is but little arched, in this contrasting strongly, c. q., with 

 goncthus, being more of the Polydesmus form. The keels typically 

 weakly protruding only at ends, the intervening" region merely con- 

 cave or in some with one weak rounded tooth or angle or sometimes 

 more. The pore is on the oblique surface at the lateral border less 

 than its diameter from the edge. On posterior plates the three rows 

 of tubercles are distinct and subequal but on anterior plates the middle 

 one may be more weakly developed and sometimes almost ol)literated. 



Head strongly tuberculate throughout. Antennae heavy. 



Color deep brown, prozonites somewhat paler; lateral borders of 

 keels light brown to obscure fulvous. 



385. Platyrril^cus gonethus, sp. nov. 



Type.— M. C. Z. 4,981. Par.vtypes.- M. C. Z. 4,982. Solo- 

 mons: Fulakora (W. M. Mann). 



General color dark brown with extreme lateral edges of keels narrowly 

 yellowish or the lighter color sometimes not e\adent ; prozonites of same color 

 as metazonites or a hghter brown, in immature specimens often whitish. 



