. Biologisches Zentralblatt. Biology. 674 Lönnberg, Variation and distilbution of tlie smooth snake in Sweden, kuowii limits of Variation in nuniber of ventral shields are 153—199 and of subcandal shields 42—70 and thus tlie swedish specimens are iutermediate forms in this respect. The shape of the plates of the head is varying- as well, and above all, the rostral has a diiferent shape in diflferent specimens. As Bon- leng-er has stated, the \fn'. fitzingeri is not only confined to Italy, but is found later in Portugal, Spain and Austria, and even in Eng- land. In Nr. 1, 3, 5 and 7 of the abov
. Biologisches Zentralblatt. Biology. 674 Lönnberg, Variation and distilbution of tlie smooth snake in Sweden, kuowii limits of Variation in nuniber of ventral shields are 153—199 and of subcandal shields 42—70 and thus tlie swedish specimens are iutermediate forms in this respect. The shape of the plates of the head is varying- as well, and above all, the rostral has a diiferent shape in diflferent specimens. As Bon- leng-er has stated, the \fn'. fitzingeri is not only confined to Italy, but is found later in Portugal, Spain and Austria, and even in Eng- land. In Nr. 1, 3, 5 and 7 of the above nientioned specimens the upper portion of the rostral measures fiilly two thirds or more of its distance from the frontal. Thus these specimens come within the limits of the mentioned variety which at the same time gets reduced to merely an individual variety instead of its former rank as a geographical one. In the other specimens the upper portion of the rostral measures from one third to one half of its distance from the frontal. According to Boulenger on his specimens the character from the rostral is com- pletely deprived of any correlative of any other, either in the lepi- dosis or in the coloration, and this is the case with the Upsala speci- mens too. The shape of the frontal is diiferent as well, sometimes nearly triangulär Avith the base forwards sometimes hexangular with anterior angle. Other plates are normal in number and shape in all 8 'J'hiee ligures showing different stages of developmeut of the rostral plate in swedish specimens of the smooth snake. The coloration is different however in different specimens. Six') specimens are grayish brown with a double row of dark spots on the back, and a row of smaller similar spots on each side. Sometimes there is a lighter stripe on the back between both rows of spots. Often there is a dark stripe on each side of the head from nostril through eye, extending on the sides of the neck corresponding to the
Size: 1545px × 1618px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectbiology, bookyear1895
