Science-gossip . ut through the second and thirdjoints, the first not being in the same the head is covered with two kinds ofpigmented hairs; the finer and smaller appear tobe nothing more than clothing, but the larger onesare hollow, their lumen continuing through thechitinous wall of the joint. The interior of thejoint is lined with epithelium, the ends of thecells being drawn out and projecting into the lumenof the hairs. This is distinctlv shown in thin SCIENCE- GOSSIP. 123 sections in which the epidermis is somewhat de-tached from the epithelium during manipulationof the
Science-gossip . ut through the second and thirdjoints, the first not being in the same the head is covered with two kinds ofpigmented hairs; the finer and smaller appear tobe nothing more than clothing, but the larger onesare hollow, their lumen continuing through thechitinous wall of the joint. The interior of thejoint is lined with epithelium, the ends of thecells being drawn out and projecting into the lumenof the hairs. This is distinctlv shown in thin SCIENCE- GOSSIP. 123 sections in which the epidermis is somewhat de-tached from the epithelium during manipulationof the sections. From the nerve numberless fibresare seen to enter the epithelium lining, but beyondthat I have been unable to trace them. By using amore suitable stain the nerve-fibres may possibly betraced through the epithelium, or the epidermisitself may be endowed with the same con-ducting power as the nerve-fibres. From thisrich supply of nerve-matter it is pretty clearthat the large hairs must be the seat of some. Fig. 5. Anterior Thoracic Spir.^cle of Musca romiioria. sensation ; but what sense they represent is verydifficult to prove from experiment, because anotherquite different sense-organ is intermingled withthem. It is highly probable that they are tactile,though this term is very vague, for it implies thesuggestion of either cold or heat, humidity ortouch, etc. ; therefore further proof is most highly developed tactile hairs are those
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Keywords: ., bookcentury1800, booksubjectnaturalhistory, booksubjectscience
