. Evolution and disease . Fig. 43.—All Egyptian Goat {Hircus thebaicus), with cervicalauricles. goats, and sheep. Yet little has been done to supporthis observations. As a matter of fact, these pendulousbodies are extremely common in the necks of goats ;few persons seem to notice them until their attentionis particularly drawn to them. 86 E VOL UTION AND DISEASE. A well-marked specimen of cervical auricle in a goatis sketched in fig. 42 : these auricles arc situated at aspot corresponding to the external orifice of the thirdbranchial slit of the embryo. The auricles are not confined to any par
. Evolution and disease . Fig. 43.—All Egyptian Goat {Hircus thebaicus), with cervicalauricles. goats, and sheep. Yet little has been done to supporthis observations. As a matter of fact, these pendulousbodies are extremely common in the necks of goats ;few persons seem to notice them until their attentionis particularly drawn to them. 86 E VOL UTION AND DISEASE. A well-marked specimen of cervical auricle in a goatis sketched in fig. 42 : these auricles arc situated at aspot corresponding to the external orifice of the thirdbranchial slit of the embryo. The auricles are not confined to any particular speciesof goat; the one sketched above is a cross between a ^/. ^?d Fig. 44.—Magnified view of a section of a cervical auricle remov-edfrom a babys neck. C, cartilage ; M, muscle-fibre ; F, fat. Nubian and a common goat. In fig. 43 a sketch isgiven of the head of an Egyptian goat {Hirciis tJiehaicus),made from life by Mr. R. E. Holding from a si^ecimenwhich was living in the Jardin des Plantes, existence in the pig has been recorded, and ahorned sheep with two well-marked cervical auriclesis figured on page d^. VESTIGIAL STRUCTURES. 87 It has been doubted whether these pendulous bodiesare of the nature of auricles, and it is desirable thatthe evidence should be put before the reader whichfavours such an interpretation. An auricle, or pinna,may be defined as an enlarged operculum in a mam-mal, consisting of a framework of yellow elasticcartilage covered with skin, simi-lar to that on the rest of thebody, and containing stripedmuscle-fibre. The cervical auricle, such asis seen in the neck of the girl on page 83, agrees with this KALEVI
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectabnormalitieshuman
