Notes on differences between some external and skull characters of Microtus arvalis (Pallas, 1778) and of Microtus agrestis (Linnaeus, 1761) from the Netherlands

• Main Author: Dienske, H.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: 1969
• Subjects: 42.84; Microtus arvalis
• Online Access: http://www.repository.naturalis.nl/record/318314; http://www.repository.naturalis.nl/document/149600

CONTENTS Introduction . 83 The identification of the sampled specimens. 85 The variability of the studied characters. 90 ι. The external characters. 90 a. The coat colour. 90 b. The length of hairs. 91 c. The length of the meatal lobe of the ear. 91 d. The tail. 92 e. The feet . 93 2. The shape of the molars. 93 3. The characters of the skull. 102 4. The characters of the mandibles. 105 5. Skull with mandibles. 106 6. Skin with skull and mandibles . . 106 Diagnoses of Microtus arvalis and Microtus agresüs. 106 References. 107 INTRODUCTION A number of characters has been used by several authors to seperate Microtus arvalis (Pallas, 1778) from Microtus agrestis (Linnaeus, 1761). Husson (1962: 27-28, 33) enumerated several characters of these forms to identify skull remains from owls pellets found in The Netherlands, Belgium and Luxemburg. Frank (1953) and Van Wijngaarden (1956) gave some external characters useful in field work. Unfortunately, none of these characters separates the two species completely and using them it is therefore