TERRESTRIAI, ACAEl OF THE TYNK PROVINCF, 69 



109. Cosinolaelaps styliferus, Halb. 473 /x. 



Ireland, with Las ins flavtis. 



no. Cosmolaelaps vacuus, Mich. 67. 



Ninebanks, with Lasius niger. 



Ireland, with Lasius niger and Mynnica scabrinodis. 



OOLAELAPS, Berl. 



Type .• oophilus, Wasm. 



I Posterior dorsal setae longer and stronger ... ... oophilus, 



,, hardly longer than the rest ... montamis. 



Myrmecophilous, Digits of mandibles small, nearly 

 edentate (?). 

 III. Oolaelaps oophilus, Wasm. 66, 67. 



Quite abundant with Formica fusca : less so with 



F. riifa, 

 X12. Oolaelaps montanus, Berl. 66,67. 



With Formica fi/sca, Myrmica spp., &c. The only 

 species commonly found with Myrmica in West 

 Allendale. 



Ireland, with Formica fusca. 



G. — Sub-family Gamasinae. 



Sexual dimorphism of the second pair of legs is the great 

 characteristic of this group. In rare instances the fourth pair 

 also is affected, and in the titular genus the dorsal scuta. The 

 latter is usually associated with a difference in general body- 

 form, as well as the general difference in adze. 



1. Parasites of mammals ... ... ... Haemoganiasus. 



Living at large* ... ... ... ... ... 2 



2. Tarsi i without ambulacrum ... ... ... ... Macrocheles. 



All tarsi with the usual ambulacrum .. ... ... 3 



3. Lobes of pulvillus lanceolate acute (littoral species) 4 

 Ambulacrum normal in form ... ... ... ... 6 



4. Dorsal scutum undivided ... ... ..'. ... Hydrogamasus. 



Dorsal scuta 2 ... ... ... ... ... ... 5 



* Migrant nymphs of species frequenting manure, carrion, and bees' 

 nests are often found, sometimes in great number, on insects. 



