A total of 598 Austrian and 1117 Polish skulls of brown hares Lepus europaeus Pallas, 1778 was examined for dental anomalies, occurrence of Wormian bones and formation of a fenestra in the fossa mandibularis ossis temporalis. In addition, the degree of ossification of skull sutures and frequencies of traceable interparietal sutures were analysed in Austrian hares. Frequencies of missing M3 were 1.95% for Austrian and 2.1% for Polish hares from 1986 - 1990. No significant differences as to age or sex were found for incidences of missing M3; the left side of the tooth row was significantly more often affected by missing M3, which indicates directional asymmetry. metry. Rotation of the I2 (mainly of low magnitude) was noticed in 27.9% of subadult and adult Austrian hares. Occurrences of all other dental anomalies such as abnormal shape of M3, missing I2, missing M3, supernumerary I2, additional upper molar and various cases of malformation or irregular position of teeth were very low, respectively. Ossification of skull sutures was presently reduced as compared to the material investigated by Cabon-Raczynska (1964) and regional differences in the degree of sutural obliteration were found. Temporal fenestration was encountered in 24.6% of subadult and adult Austrian hares and in 11.6% in Polish hares sampled during 1986 - 1990 (p < 0.001). Frequency of temporal fenestration increased with age: 2.9% in fetuses/neonates, 16.5% in subadult and 28.1% in adult hares from Austria (p < 0.01, d.f. = 2); 8.7% in subadult and 23.8% in adult Polish specimens. Average frequency of Wormian bones in Austrian hares was 4.8% and 4.4% in the Polish material. Within subadults 3.7% of males and 16.3% of females (p < 0.01) exhibited a traceable outline of the os interparietale.