Horváth Géza (szerk.): A Magyar Természettudományi Múzeum évkönyve 24. (Budapest 1926)
Éhik, Gy.: Magyarország földipockai
new food has been put in their cage in order to taste it at least and to store it up. I put a small wooden case in their cage to hide themselves in, which cage they filled up so much with Indian corn that they were almost unable to get into the case full of food. They ate only the soft parts of the corn, the germ, but they accepted willingly also other kinds of grain forage, even certain green food. I could not get them for copulation, although my Microtus arvalis specimens kept in the same conditions gave birth to many young voles. My animals died after a captivity of three months in inflation due to the contortion of bowels. Remarks to the characters of the species. MILLEE classifies the European Pitymys-es into 3 groups 1 : he distinguishes a subterraneus, a Savii and an ibericus group. According to his determination key, the subterraneus-gTOup can be subdivided into two undergroups. In one of this undergroups the depth of the brain-case, including auditory bullae about 65°/ 0 , in the other one 70% of occipital breadth. An error of O'l millimeter in measuring means an error of 1%, and it is very possible to commit an error of O'l millimeter even with the most accurate dial caliper. If I commit an error in each of my measurements, then considering that I have to undertake at least two measurements, the error in percentage is at least 2 °/ 0 , but usually more than that, considering that it is extremely difficult to measure accurately the depth of the brain-case including also the height of auditory bullae. MILLEE omits to define accurately in his work also what he means by the depth of the brain-case. From what point and how does he measure it? According the testimony of my repeated measurements I get different results if I take the lower edge of the auditory bullae and the top of the skull between the two arms of the caliper, due to the fact that the topmost point of the skull being nearer to the point of the nose than the auditory bullae, I have to measure a transverse diagonal and the micrometer set to eyesight is not absolutely accurate giving a different result at every measurement. So it is impossible to measure directly, since I have to measure a transverse diagonal, and our eyesight is not reliable at a so low limit. Therefore with the methods mentioned, although I had to take but two measurements, the error is really more than 3%. With such a comparatively great error it is impossible to determine which undergroup our animal belongs to. 1 As quoted above . p. 753—754. !
