84 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I28 



invariably was very heavily parasitized with chiggers, carrying an 

 average of at least 250 chiggers per individual. Samples of 25 to 75 

 chiggers from 32 such Hylomys have failed to yield any Gahrliepia. 

 Twenty-nine of these Hylomys had been examined carefully by means 

 of the dissecting microscope and particular attention paid to known 

 anatomical sites for Gahrliepia, as along bases of hairs of the snout 

 and in or on the perineum. On the other hand, certain of the rats, 

 particularly Rattus whiteheadi and R. alticola, living in the immedi- 

 ate vicinity were parasitized with Gahrliepia, as shown in table 3. 

 The tree shrews, Tupaia montana baluensis Lyon, frequently trapped 

 or shot on the ground in the same environment as the Hylomys and 

 Rattus, never carried Gahrliepia even though inevitably very heavily 

 infested with chiggers. Many specimens of Tromhicula and Euschon- 

 gastia were collected from ground-dwelling and tree-dwelling squir- 

 rels, but no Gahrliepia were ever taken, as noted in the table. The 

 absence of Gahrliepia on tree-dwelling squirrels may be partially 

 ecological in nature. 



The subgenus Gahrliepia in general exhibits much the same sort 

 of host preference as indicated for the Borneo species just discussed. 

 We have been able to locate a total of 720 ^^ actual specimens or 

 individual specific determinations of Gahrliepia in the literature. Of 

 these, 462 specimens (64 percent) were from various species of rats; 

 107 (15 percent) were from shrews, 114 (16 percent) were from 

 Tupaia, a tree shrew; 14 specimens were from moles; 31 from 

 ground-dwelling squirrels (Menetes and Lariscus) ; one from an 

 African bat (i.e., G. nanus), and one from a Malayan Hylomys. It 

 will be noted that no specimens are listed as having been from am- 

 phibians, reptiles, birds, or tree squirrels. However, Gater mentions 

 an unspecified number of G. fletcheri as having been collected on the 

 tree-dwelling Callosciurus caniceps Gray. The other references in 

 the literature, which cite only hosts and do not include data on num- 

 bers of specimens, all mention only ground-dwelling rodents or insec- 

 tivores as hosts. Despite the fact that Gahrliepia specimens are col- 

 lected only relatively infrequently, as compared to Tromhicula and 

 Euschongastia, it is safe to conclude that the subgenus mainly para- 

 sitizes rats, mice, shrews, and tree shrews, and rarely if ever occurs 

 on tree squirrels or birds or cold-blooded vertebrates. 



The subgenus Gahrliepia includes a relatively high proportion of 

 species that have been found only in the primary forest. Although 

 these species have been collected only infrequently, it is probable that 



^s It is reiterated that this number refers to individual specimens or records 

 of such, and not to numbers of collections or to hosts. 



