Evenings at the microscope; or, Researches among the minuter organs and forms of animal life / by Philip Henry Gosse.

  • Philip Henry Gosse
Date:
1895
Catalogue details

Licence: Public Domain Mark

Credit: Evenings at the microscope; or, Researches among the minuter organs and forms of animal life / by Philip Henry Gosse. Source: Wellcome Collection.

    183/464 (page 163)
    THE SUCKER OF A BUTTEKFLV. A small portion of one half- cylinder. upper lip, forming two blunt points. Below this is the pair of strong brown mandibles, convex outwardly and concave inwardly, each cut at its broad biting edge into several teeth. Below these are two little points which represent the maxillce, and between them a blunt rounded knob, which is the lower lip (labium). You may also see on each cheek, close to the base of the mandible, a little pit, out of which rises a short columnar organ tipped with two bristles; these columns are the incipient antennce. Outside them you may discern, on each cheek, a series of six globes of glass (so they appear) set in the substance of the skin—five forming a semicircle, and one in the centre ; these are “ the windows at which the [silkworm’s] soul looks through ”—provided he has any soul; in prosaic parlance, his eyes. Now, having thus introduced the several members of our useful friend’s physiognomy to you, let me call your attention to a fleshy wart just beneath the lower lip, and midway between the bases of the two fore legs. This wart terminates in a horny point not unlike a bird’s beak, which is perforated, and from the tip of which the glistening yellow filament of silk is ever drawn out, as the caterpillar throws his head from side to side. This pointed wart is the spinning organ ; and the thread of silk is, as it issues from the orifice, a fluid gum, which hardens immediately on its exposure to the air. The silk gum is secreted by the caterpillar in two long blind tubes, which lie twisted and coiled in the interior of the body, occupying nearly the whole space, except that which is taken up by the great digestive canal. These