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unusual species is Neogovea mexasca; this is the onlytroglobitic cyphophthalmid in the !\ew World and theonly species recorded for lVlexico or Central America.Huautla de Jimenez, Oaxaca.-This region is a highplateau located near the town of Huautla de Jimenezin northern Oaxaca near the Puebla border. Thisplateau, at an elevation of about 2,000 meters, isbounded on the south by the valley of the Rio SantoDomingo at an elevation of less than 350 meters, onthe north and west by the valley of the Rio Coyomeapanand the Rio del Camaron, and on the northeastby the Miguel Aleman Reservoir at an devation ofless than 100 meters (A nonymous, 1965). The greatestdevelopment of karst has been in the hil!her partsof the plateau to the cast and southeast of Huautlade Jimenez. Most of the drainage on the plateau isinternal. the water emerging from springs in the rivervalleys more than 1,500 meters below. Karst formspresent on the plateau include lapiez, pinnacles, andlarge dohnas. :Vlany of these dohnas contain pits, andthe larger-such as that in which Sotano de San Agustinis found-are more than 100 meters deep and onekilometer lonl!. The maturity of the karst, the greatlocal relief, anrl massivl~ Crdacl~oUS limestone haveprovided the facLors necessary for the developmentof extensive integrated caVI~ syst(~ms. The larger cavesinclude Sotano de A~ua de Carrizo. La Grieta, Sotanodel Rio Iglesia, and Si,tano de .::lan Agustin. The lastcave has a depth of more than 1,000 nwters and isalllong the deeper in the world. ,\dive streams flowthrough tlw deep caVI~S. Russell (1965), Fish andI{ussell (1966), Boon (1969). ~tone (1977, 1979a).and Steel (1978) describe SOUle of the caves. Inaddition to caves on the platcllu, several caves in thevalley of the Rio Coyomeapan have heen studied.These are generally small, horizontal caves with arich fauna.The invertehrate fauna of the rqrion. thou!!h stillpoorly known includes -l6 identifil~d species. ofwh idl f~iO"htr:':'an~ trfwl ohi tes. Tlw tnwlobi tic fauna~ ~inrludes a scorpion of Iincertain affinities. an undescribedtarantula of tht:: geluls Schi::opelma, anundescribed phokid spider of the /!enu~ Pholcophora,the ckidogonid millipl~d Cll'idof!ona baroquaShear, the l:ambalid Inillipl'dllexicam bala fishiCallsey, the collemholan J'seudosinel/a bonita Christiansen,an IIndescrihed i'l'llIIS and ,;pecies of nicoletiidthysanllran. and L1", carahid beetle Platynus(Mexisphodrus) llrqllijoi (Ilendrichs and Hoi ivar). Thetruglobites all hdon/! to i'enera known from theSierra \Iadre Oriental as well as ()ax aca and Puehla.The tro/,Iophile fallna. tholl/!h poorly known taxonomically,bdol1l!s. as ooes the troglouite fauna, togroups common both in southern \Iexico and theSierra Madre Oriental. Species included are a schizomidof the genus Schizomus; an amblypygid of thegenus Paraphrynus; ctenid spiders of the genus Ctenus;mysmenid spiders of the genus ]l,Jaymena; thenesticid spiders Eidmannel/a pallida (Emerton) andGaucelmus calidus Gertsch; pholcid spiders of thegenera Coryssocnemis, Metagonia, and Modisimus;opilionids of the genera lloplobunus and Karos;the rhachodesmid milliped Rhachodesmus digitatusCausey; sphaeriodesmid millipeds of the genusSphaeriodesmus; campodeid diplurans; collembolansof the genus Pseudosinella; carabid beetles of thegenus Platynus; and staphylinid beetles of the genusBelonuchus.San Sebastian de las Grutas, Oaxaca.~This regionis located in the Oaxaca Upland to the north of Solade Vega. It comprises an ill-defined area of Cretaceouslimestone at elevations of 1.800 to 2,100meters. Karst development consists principally oflarge shallow dohnas. Two of the caves studied aresmall pits and a third is a small horizontal cave. Thefourth cave, Grutas de San Sebastian, is a large,essentially horizontal cave with a large stream in alower level.The troglobitic fauna includes an undescribedmilliped of the family Triehopolydesmidae, an undescribednicoletiid thysanuran, and a collembolanof the genus Acherontides. The troglophile faunaincludes the endodontid snail lIelicodiscus singleyanus(Pilshry), a schizomid of the genus Schizomus,the Inysmenid spider Maymena delicata Gertsch, thenesticid spider Caucelmus augustinus Keyserling, apholcid spider of the genus Physocyclus, the opilionidHoplobunus oaxacensis Goodnight and Goodnight,and a pyrgodesmid milliped of the genus Myrmecodesmus.These species all helong to genera commonto the eaves of southern Mexico.Santiago Apoala, Oaxaca.-This is a little-studiedarea of limestone karst located about 20 kilometersnortheast of Asuncion \ochixtlan in northern Oaxacaon a high plateau at an e1f~vation of about 2,240meters. Karst development consists of numerouslarge, shallow rlolinas. from a few of which pitsdescend. Drainage appears to be almost entirely internal,but no large integrated systems have beendiscovered. Of the six caves visited only two are ofany great extent. One of these, Comedor del Diablo,is a deep vertical system still poorly explored; theother, Cueva de Apoala, is loeatt~d more than 200meters below the edge of the plateau and consistsof a large passage from which a stream emerges. It isalso poorly explored.Tht~ cave fauna of this rather isolated region ispotentially of considerable interest, but it has been43