. British beetles: an introduction to the study of our indigenous Coleoptera. Beetles. 22 BRITISH BEETLES. mastication, etc., is. Fig. 3. Upper side of head of D. margi nalis {highly magiiijied). it being absolutely necessary to understand tliera in working from descriptions. The liead, bearing the eyes, antennae, and organs of the first to be considered. The accompanying cut of the head of a Water-beetle will show the chief points to be no- ticed on the upper side : here, a is the labrum or upper lip; h, the clypeus or shield of the mouth, often bearing tubercles or even horns ; c or d are th
. British beetles: an introduction to the study of our indigenous Coleoptera. Beetles. 22 BRITISH BEETLES. mastication, etc., is. Fig. 3. Upper side of head of D. margi nalis {highly magiiijied). it being absolutely necessary to understand tliera in working from descriptions. The liead, bearing the eyes, antennae, and organs of the first to be considered. The accompanying cut of the head of a Water-beetle will show the chief points to be no- ticed on the upper side : here, a is the labrum or upper lip; h, the clypeus or shield of the mouth, often bearing tubercles or even horns ; c or d are the mandibles or upper jaws (these are dis- sected out in the figure, and d is reversed) ; e e, the eyes; /, the base of the antennse; g, the vertex or crown, and h the occiput. The mandibles are hard and sharp, often (as in the male of the Stag-beetle) very much developed. The eyes, which are composed of many facets,, situated on the side of the head, and usually large, are normally two in number, being however in some cases aberrant; for instance, in Dorcus (the small Stag-beetle), each eye is almost divided into two, being interrupted by the lateral ridge of the head ; and in the Gyrini (the ''Whirlwigs^^), it is distinctly divided by a deep broad channel, containing the antenna, so that the insect is four-eyed, having two on the upper and two on the under surface,—an admirable structure for species that pass their lives on the top of the water, and need extra sharpness of vision, partly to save themselves from foes above, and partly to detect their own food Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Rye, Edward Caldwell. London, L. Reeve & Co.
Size: 1561px × 1600px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1860, booksubjectbeetles, bookyear1866
