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of the genus Lutzomyia has not been reported out·side of southern Belize. The miJIiped R. cryptymoidesis also the only cavernicole recorded for that genus.Caves Branch, Cayo, Belize.-This region is locatedin central Belize north of the Maya Mountains. Theterrain is characterized by well-developed cockpitkarst, with hundreds of steep hills separated by enclosedvalleys. Drainage is almost entirely subterraneanand numerous major caves are found in theregion. The caves are formed in Cretaceous limestoneand occur at elevations from 40 to 120 meters(Dixon, 1957; Graham et al., 1980). Caves Branch isa stream flowing off the Paleozoic rocks of the MayaMountains, across the karst surface eventually toenter the Sibun River. For about three kilometers ina direct line, and much more underground, it passesthrough a major cave, the Caves Branch Cave System.Most of the caves in the area have numerous ent·rances, known locally as breakou ts, where collapsehas opened the underground stream passage to thesurface. Footprint Cave, a major cave, has only oneentrance but more than seven kilometers of surveyedpassage and includes both an upper-level dry area anda lower active stream passage (Graham et al., 1980).The Caves Branch region is still inadequatelystudied bIOlogically, but 33 species, including seventroglobites, have been identified. The troglobitesinclude the vachoniid pseudoscorpion Vachoniumbelizense Muchmore, an undescribed schizomid ofthe genus Schizomus, an undescribed species ofcharontid amblypygid, the pholcid spider Melagoniajarmila Gertsch, the opilionids Cynortina misticaGoodnight and Goodnight and Stygnomma peckiGoodnight and Goodnight, and the cambalid miJIipediarmilka alba Shear. This fauna is particularly inte·resting in that it contains several quite distinctiveelements. The charontid amblypygid is the only trog·lobitic representative of this family in North America;the opilionid genera Cynortina and Stygnomma arenot otherwise known to have troglobites on mainlandNorth America; and iarmilka alba is an aberrantmember of a family not otherwise known south ofOaxaca, Mexico. The pseudoscorpion genus Vachoniumis known only from caves in the Yucatim Penin·sula and Belize. The remaining troglobites, as well asthe troglophiles, are all typical members of the caver·nicole fauna of southern Mexico. Troglophiles ofinterest include the spiraxid snail Streptostyla meri·dana meridana (Morelet), the amblypygid Paraphry·nus raptator (Pocock), the mysmenid spider May·menu mayana (Chamberlin and Ivie), ochyroceratidspiders of the genera Ochyrocera and Theotima, anopilionid of the genus Stygnomma, the pyrgodesmidmilliped Myrmecodesmus unicorn Shear, and theleiodid beetle Ptomaphagus (Adelops) barbarae Peck.Cobin, Alta Verapaz. Guatemala.-This region islocated in the vicinity of the town of. Coban insouthwestern Alta Verapaz. The terrain in much ofthe region is characterized by a mature karst withnumerous uvalas, dolinas, and solution valleys and byalmost complete internal drainage. The principallimestone unit in the area was mapped by Walper(1960) as undifferentiated Ixcoy and Coban Formations.Only four caves have been studied with respectto their invertebrate fauna. One, Cueva Chirrepeck, islocated to the south of Coban; two, Grotte C3 andGrotte G3, are in the Sierra de Pampur to the west ofCoban; and the third, Cueva Chiacam, is in the Sierrade Chama to the northeast of Coban. Nothing isknown of the nature of Cueva Chirrepeck, but theremaining caves are described in Delamare Deboutteville(1976) as being small and containing water.Most of the collecting in this region was done bySwiss and French biospeleologists and reports onmost of their material have not yet been published.The eighteen species which have been identified includefive troglobites and several troglophiles ofinterest. The troglobites are the pseudothelphusidcrabs TyphLopseudothelphusa juberthiei DelamareDeboutteville and T. mitchelli Delamare Deboutteville,the chthoniid pseudoscorpion Paraliochthoniusstrinatii Beier, the trichopolydesmid milliped Chirrepeckialyncilecta Hoffman, and the campodeid dipluraniuxtlacampa hauseri Conde. The crab genusTyphlopseudothelphusa is otherwise known only bya species in Chiapas and the dipluran genus iuxtlacampaby a species in Guerrero. Chirrpeckia is amonotypic genus and P. strinatii is the only troglobitein the genus in North America. Troglophiles ofinterest include the neobisiid pseudoscorpion Ideobisiumsimile Balzan, the mysmenid spider Maymenamayana (Chamberlin and Ivie), the nesticid spiderGaucelmus strinutii Brignoli, the opilionid Arganotusstrinatii Silhavy, and the pyrgodesmid millipedSynoptura petrinus (Hoffman). The last three speciesare endemic to this region, but otherwise the fauna istypical of southern Mexico.Lanquin. Alta Yerapaz. Guatemala.-This regionis located in east-central Alta Verapaz in the vicinityof the town of Lanquin. The geology, with specialreference to karst morphology and speleogenesis, hasbeen discussed by Smith (1968). The principal cavebearingformations in the area are the Campur Formationof Cretaceous age and the Chochal Formation,probably of Permian age. The largest cave in theregion, Grutas de Lanquin, is formed in the CampurFormation. The terrain is typical of many tropical52