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The essential characters of the anomalepid snake genus Liotyphlops are found in its osteology, scale rows, numbers of dorsals, size, and head scale arrangements. The twelve currently recognized species of Liotyphlops are reduced to five through the analyses of variation of all available specimens in the Genus. Liotyphlops caracasensis, L. cucutae, L. guentheri, L. incertus, L. metae, L. petersi, and L. rowani, are placed in the synonomy of other species. One currently recognized synonym, L. beui, is removed from synonomy and recognized as a separate species. A new species is described from the Rio Magdalena basin of Colombia, and one individual from Brazil represents an apparent new species, but is not formally described in this paper. Other species of Liotyphlops recognized by us areL. albirostris, L. anops, L. schubarti, L. ternetzii, and L. wilderi. Variation in lateral head scale arrangements is documented for a large series of L. albirostris from Panama. Head scale variations, variations in numbers of scale rows about the body, and absence ofan unified method of labeling head scales has produced an excessive number of synonyms for the species of the genus. A new method for labeling lateral head scales of Liotyphlops is proposed, the entire distribution ofthe genus is clarified, and a key to the species is presented.

With 12 figures in the text)Reproduction and growth of two species of congeneric fruit bats, Cynoprerus minutus and C. brachyotis, were studied in Brunei, northern Borneo. C. minutus is smaller and inhabits rainforest; C. brachyotis is larger and inhabits non-rainforest habitats (secondary forest, mangrove forest, deforested zone). The two species were sympatric only at Batang Dun, a village near rainforest.The climate of the study area is characterized by uniformly high temperatures and rainfall, but relatively there are two seasons of more rain and two of less rain. Reproduction of both species is seasonal with continuous bimodal polyoestry. Within each species, the females are in reproductive synchrony, with young born in two distinct seasons (3-4 months each) of parturition 5-7 months apart. Each parturition is followed by postpartum oestrus. For each species, gestation spans about 5-6 or 5-7 months, with embryonic development delayed in the early stages. Births of neither species were timed to the seasons of greater rainfall or to the general season of flowering/fruiting of trees.Instead, births were centred about the two seasons of less rainfall and probably timed to the fruiting of certain species of trees, including mangoes for C. brachyotis.The weight data for C. brachyotis indicated a difference in diet between adult males and females.The bimodal pattern of weight increase/decrease for adult males corresponded to the bimodal cycle of ripened mangoes in Brunei. Although weight increase/decrease for adult females did not correspond to the bimodal cycle of ripened mangoes, none the less the two birthing seasons did, following shortly after or beginning at the two times of abundant ripened mangoes. Similarly, adult males and females of C. minutus appeared to have different diets and/or different foraging patterns.Both sexes of C. minutus (and probably also of C. brachyotis) attain maturity at about 7 months, with females giving birth for the first time at about 12 months. Females conceive shortly upon attaining sexual maturity and are thereafter in states of essentially continuous reproduction with two young born annually (2 littedyr, 1 neonatehirth). Relative to other fruit hats (Mickleburgh, Hutson & Racey, 1992), C. minutus and C. brachyotis have high rates of reproduction.

A representative sample of waterways in Liberia was surveyed for crocodiles, and all three species of African crocodiles were observed. Contrary to previous reports, only Nile crocodiles inhabit the Monrovia mangrove swamps and brackish-water mouths of rivers; there are no slendersnouted or dwarf crocodiles in these habitats. There is partitioning of habitats among the three species in Liberia: Nile crocodiles in mangrove swamps and river mouths (brackish water); slendersnouted crocodiles in rivers through rain forest (freshwater); and dwarf crocodiles in small streams through rain forest (freshwater), some entering the adjacent river. Dwarf crocodiles utilize burrows in the stream banks.Nowhere are crocodiles abundant, and there is an apparent absence of adults. Although 40% of Liberia is forested, deforestation is occurring rapidly by foreign timber companies and slash-and-burn agriculture practised by the largely rural population. Hunting with firearms, although illegal, is widespread, both for subsistence and commercially, without concern for depletion. Mangrove ecosystems near human population centres are being destroyed. The combination of the above factors has apparently depleted the crocodile populations in Liberia.

The reproductive cycle of the Nile crocodile (Crocodylus niloticus) was studied in Zimbabwe. Females attained sexual maturity after they had reached a total length of about 262 to 287 cm and males, 270 to 295 cm. Some adult females did not reproduce every year. Follicle growth and vitellogenesis occurred from April to mid August during the dry winter. During this time reproductive females had elevated levels of plasma oestradiol‐17β, testosterone, calcium and magnesium, but lowered levels of iron. The measuring of plasma calcium was an ‘early pregnancy’ test, reliable up to four months before nesting. Elevated levels of plasma testosterone in reproductive females corresponded to the time of courtship and mating. Ovulation occurred during the latter half of August. Males had viable sperm from mid May to mid September, during the winter. Courtship and mating occurred from late June to mid August, when crocodiles were confined to pools. Females nested on the higher sand ridges in the dry river bed from early September to early October, and eggs hatched during December.

Sibon sartorii, S. annulifera and S. zweifeli are more closely related to each other than to any other species of Sibon, and together they comprise the sartorii group. The sartorii group is distinguished by the shared characteristics of: 1) cylindrical body; 2) dorsal scales of equal size; 3) dorsal pattern of black bands alternating with light bands of red, orange, yellow, beige, cream or white; 4) 6-12 maxillary teeth; 5) 10-16 dentary teeth; and 6) non-protruding eyes of small to moderate diameter. Geographic and non-geographic variation in the species are analyzed. Colors of light bands and collars of S. sartorii cannot be used as a characteristic to diagnose subspecies because of the tremendous variation throughout its range. S. sartorii has two valid subspecies, the nominate form and S. sartorii macdougalli. Data are presented for inclusion of Tropidodipsas sartorii annulata in the synonymy of S. s. sartorii. S. annulifera is monotypic, and S. zweifeli is known from only two specimens.

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