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The principal cavernous fonnation in the region isthe Ixcoy Limestone of Cretaceous age. Elevationson the plateau range from 2,500 to 3,300 meters.Most of the caves art~ small and many take the flow ofsmall streams. Sbordoni et al. (1977) described thecaves which have been studied.The Italian biospeleologists who studied thisregion have yet to publish most of the results of theirwork and only 13 species have been identified todate. The aquatic fauna includes two endemic species,the asellid isopod Caecidotea mitchelli Argano andthe bogidiellid amphipod Bogidiella pasquinii Ruffoand Vigna Taglianti. The terrestrial troglobites arethe philosciid isopod Colombophiloscia cavernicolaVandel (also known from Venezuelan caves) and thecarabid beetle Mayaphaenops sbordonii Vigna Taglianti.TroglophiIes of interest include the hyalellidamphipod Hyalella azteca (Saussure), a pyrgodesmidmiIliped of the genus Synoptura, and a carabidbeetle of the genus Paratrechus.Montafias de Cuilco, Huehuetenango, Guatemala.­This region is located in southwestern Alta Verapazsouth and southwest of the town of La Libertad. Thetop of the Montanas de Cuileo forms a plateau atan average elevation of about 3,000 meters. The fivecaves visited occur at elevations of 2,880 to 3,120meters. The geology of the northern part of theregion has been studied by Boyd (1966), Davis(1966), and Anderson (1967). A geologic map of theregion has been published by the Guatemala InstitutoGeogritfico !\acional (1967, 1968a). The principalcavernous fonnation in the area is the Ixcoy Limestone(sometimes not differentiated from the CobanFormation) of Cretaceous age. Karst development onthe plateau is primarily dolina karst with almostcomplete internal drainage. This region has been littlestudied speleologically and few caves are known. Allof the caves which have been biologically investigatedare small, shallow pits with little horizontal extent.The fauna of this promising region is essentiallyunknown and only five species have been identified.No troglobites are known, and the only probabletroglophiles are an undetermined species of millipedof the family Peridontodesmidae, a rhachodesmidmilliped of the genus Aceratophallus, and a staphylinidbeetle of the genus Philonthus. The rhaphidophoridcricket Hypsobadistes gracilior Hubbell, becauseof its extremely long legs and delicate body, isprobablj' restricted to the use of caves, though stilldependent on the surface for food.Santa Ana Huista, Huehuetenango, Guatemala.­This region is located in west-central Huehuetenangonear the Chiapas, Mexico, border. The investigatedkarst region is in the vicinity of the village of El Taba-cal about six kilometers west-northwest of the townof Santa Ana Huista. There has been little study ofthe area and only three caves have been examined fortheir invertebrate fauna. The principal limestone unitsin the region are the Ixcoy and Coban Fornlations ofCretaceous age. The Rio Huista sinks in a large caveknown as El Sumidero, but sumps after about 400meters. The stream re-emerges from a sump in thelargest cave in the region, Cueva de Agua Escondida;this large, treacherous stream has been surveyed foralmost four kilometers (Broughton and Boon, 1975).The only other cave for which information is availableis Cueva de las Calaveras, a small, little exploredpit about 10 meters deep (Sbordoni et al., 1977).Very little is known of the cave fauna of thisregiun and only 11 species, none troglobitic, havebeen reported. Troglophiles include the nesticidspiders Gaucelmus augustinus Keyserling and G. calidusGertsch and the endemic pyrgodesmid millipedSynoptura shawcrossi (Shear).Lago de Izabal, Izabal, Guatemala.-This region islocated in eastern Guatemala near the Gulf of Honduras.The principal city in the area is the port ofPuerto Barrios. There has been little study of thearea, with only two caves having been explored. One,Cueva de la Coche, is located near the Rio Dulceabout 2.5 kilometers from the Gulf. It is reported byPeck and Peck (1973) as being small and only about83 meters long. The larger cave, Gruta EI Silvino, islocated 34 kilometers west of Puerto Barrios to thesouth of Lago de Izabal. This cave, a map of which isin Gurnee (1962), contains more than 0.5 kilometerof dry passage, where an unexplored stream passageis encountered.Only 12 species, none troglobitic, have been reportedfor this region. Troglophiles include thegrapsid crab Sesarma (Holometopus) roberti H.Milne Edwards, the schizomid Schizomus silvinoRowland and Reddell, the mysmenid spider Maymenamayana (Chamberlin and Ivie), the ochyroceratidspider Ochyrocera formosa Gertsch, the pholcidspiders Metagonia blanda Gertsch and Ph 01­cophora quieta Gertsch, the pyrgodesmid millipedCalymmodesmus inquinatus Causey, and scydmaenidbeetles of tl1e genus Scydmaenus. This fauna is typicalof Guatemala and southern Mexico.Flores, Petim, Guatemala.-This region is locatedin central Peten south of the town of Flores. Theterrain consists of the low, rolling hills which constitutethe lowland area of the Chiapas-GuatemalanHighlands province. Although five caves have beenbiologically studied, the only one for which informationis available is Cueva Jobitzinaj, located south ofFlores. A partial map of this poorly explored cave54