. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. TrachecB from Setiparous Glands. 25 stigmata are confined io the head, large setse spring from the sides of the segments in the place where stigmata occur in all the Chilopoda and Hexapoda. This curious retention of so many primitive Annelidan characteristics on the part of the Myriapods is after all what one might expect from animals so clearly Annelidan in their rich segmentation. (2) The arrangement of the stigmata, hairs, and pigment in the pupa of the vapourer moth {Orgyi
. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. TrachecB from Setiparous Glands. 25 stigmata are confined io the head, large setse spring from the sides of the segments in the place where stigmata occur in all the Chilopoda and Hexapoda. This curious retention of so many primitive Annelidan characteristics on the part of the Myriapods is after all what one might expect from animals so clearly Annelidan in their rich segmentation. (2) The arrangement of the stigmata, hairs, and pigment in the pupa of the vapourer moth {Orgyia antiqua) is very suggestive. The deep black pigment of the skin is relieved at the sides of the abdominal segments by clear white or whitish patclies, running dorso-ventrally and nearly meeting in the ventral middle line. The arrangement is shown in the woodcut. On each side of the stigma is a very definite, more ^y ant. Lateral view of an abdominal seo;ment of a pupa of a f emaJe Vapourer Moth, showing the " parapodial ; or less circular field covered with long seta3. It is true that the greater part of the dorsal surface is covered with long setai, but no one can examine these setigerous areas under the microscope without being convinced that they are distinct regions. If this arrangement is compared with an Annelidan parapodium, the similarity in the position and arrangement of the setse is very striking. The stigma corresponds to the opening of the acicular gland and the setigerous areas to the setigerous regions of the parapodium on each side of the aciculum. It was especially the aciculum of the dorsal para- podium to which I referred the stigmata of the Hexapoda. We have here, then, traces of a complete dorsal parapodium, as shown in the figure, while beneath it is seen the dorsal part of the ventral parapodium with a similar setigerous area well marked off. More ventrally (not shown in the figure) the white patch is continued, but without setge,
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Keywords: ., bookce, booksubjectbotany, booksubjectgeology, booksubjectzoology
