400 PROCEEDINGS OF THE NATIONAL MUSEUM. voL.xxvii. 



Hind coxa? without minute teeth inside. Hind femur with but a 

 single minute hair on inside. Apical spines on second joint of hind 

 tarsi nor extending- beyond third joint. First pair of spines on tifth 

 joint of hind tarsi strongl}^ dislocated toward the median line. Lengths 

 of joints of hind tarsi in the proportion 25.5-15-8-5-9. 



Length, 3.5 mm. Color, clear brown. 



Male: Head flattened on top after the usual manner. Along the 

 front marghi of antennal groove, above the e3'e, are three or four 

 small l)ristles. There are a far greater number of minute hairs on 

 hind margin of antennal groove than in the female. 



On the meso- and metanotum and first abdominal segment occurs 

 an arrangement of bristles which is entirely unique in the whole order. 



On the side of meso- and metanotum is a tongue-shaped area, pointed, 

 backward, and common to the two sclerites. About the margin of this 

 are the bristles an-anged — especially long and numerous on the upper 

 margin. On the first abdominal segment is a similarly outlined area 

 extending backward from metanotum, though much smaller and with 

 but seven or eight lu'istles about its margin. Antepygidial bristles 

 three on each side, the outer two in each set well developed, the inner 

 aborted. 



The genitalia are very strongly and uniquely developed. The pos- 

 terior portion of the abdomen is characterized by numerous long, stout 

 bristles, gathered into two brush-like lots below, while above, the hind 

 margin of eighth segment laterally has a row of about twelve of these 

 long bristles, just behind which are a greater number of small ones. 

 The lateral portion of ninth tergite has the usual dorsal lol)e, which is 

 here long and slender; the portion bearing the two bristles just over 

 insertion of upper claspers is here narrowly produced beyond the 

 hind margin of the claspers — a very unique arrangement. The upper 

 claspers are long and slender, the upper and lower posterior angles 

 strongly roundl^^ produced, and each armed with a stout dark tooth, 

 the upper one long and bent, the lower short, straight, and accompa- 

 nied by a short bristle which stands just a))Ove it. 



Length, 2.75 mm. 



Tyj}6. -Cat. No. 6907, U.S.N.M. 



GERATOPHYLLUS KEENI Baker. 



Plate XVI, figs. 7-12. 



This species was described from specimens taken on Penrmyscus heeni 

 at Masset, Queen Charlotte Islands, by Rev. J. H. Keen. All of our 

 records for the Queen Charlotte Islands are due to this gentleman, and 

 his contributions have been most important ones. Additions and cor- 

 rections to the original description will be evident in the figures and 

 synopsis. 



