We assessed the accuracy of skeletochronology in estimating ages of Japanese clouded salamanders (Hynobius nebulosus) using the individuals whose ages (1–4 yr) are known by their cohort markings and the individuals that were consecutively captured at intervals of 4–7 yr. Skeletochronology correctly estimated the actual ages of 87.5% of individuals with known age. The errors in estimation ranged from -1 to 1 yr with an average of 0.03±0.11 (2SE) yr. In the consecutively captured samples, 77.3% of individuals were correctly estimated to age and the errors ranged from -1 to 1 yr with an average of -0.14±0.20 yr. Errors seem to be caused by either the timing of sampling bones or a rapprochement of the bone. However, our results demonstrate that skeletochronology is a valid tool for estimating individual age of H. nebulosus studied, with high accuracy and low degree of errors as a whole.

Variation in relation to age and sex in a population of Pachytriton labiatus from Mt. Huangshan, Anhui Province, China was examined. There appeared to be distinct morphological variation among age/sex groups. We suggest that some of this variation is associated with ecology and behavior. Examination of the newt species from the type locality and nearby localities of Pachytriton granulosus (=Pingia granulosa), a taxonomically problematic species, revealed that this taxon was almost indistinguishable from juvenile P. labiatus. We therefore conclude that P. granulosus is a junior synonym of P. labiatus.

The advertisement calls of three Indian frogs, Ramanella triangularis (Microhylidae), Indirana gundia (Ranixalidae), and Fejervarya rufescens (Dicroglossidae) are described. The call of R. triangularis, consisting of 30 pulses with low dominant frequency bands around 0.6 and 1.1 kHz, had a mean duration of 0.38 s, and was emitted at about 3 s call intervals. The call of I. gundia was much shorter, with a duration of only 0.1 s and was emitted at longer, rather irregular intervals. The dominant band was recognized at 1.4 kHz, and pulsation was indistinct. The call of F. rufescens, consisting of 24.9 pulses, had a mean duration of 0.46 s, and was emitted at 3.68 s call intervals. There were numerous frequency bands in its call, with dominant bands around 3 kHz. These results are compared with those of previous studies on the same and related species. Ecological observations on calling sites and behavior are also presented.

The body size and age at maturity of female Rana porosa porosa were investigated in two valley bottoms in Tama Hills, Japan. Frogs collected during the breeding season, not showing the male secondary sexual characteristics, were subjected to injection of HCG and were kept with mature males. Individuals that did not ovulate after the dosage were dissected to determine sexes and maturity status on the basis of gonadal morphology. The snout-vent length (SVL) of the smallest mature female was 58.3 mm. The clutch size ranged from 1465 to 2726, and showed a significant positive correlation with SVL. The one-year-old age group of females included both mature and immature individuals, whereas two- and three-year-old females were invariably mature.