. Lessons in nature study. Nature study. SPIDERS 107 are always directed forward, it may readily be seen that they are not used in walking. Into how many parts is the body divided ? To which part are all the legs attached ? Have the children look for the eyes of the spider. Where are they and how many are there ? The eyes of spiders are shining little black spots situated on the upper frontal part of the anterior half of the body, (that part which bears the legs, and is the head and thorax of the spider joined together). The eyes vary in number and arrangement in different kinds of spiders, an
. Lessons in nature study. Nature study. SPIDERS 107 are always directed forward, it may readily be seen that they are not used in walking. Into how many parts is the body divided ? To which part are all the legs attached ? Have the children look for the eyes of the spider. Where are they and how many are there ? The eyes of spiders are shining little black spots situated on the upper frontal part of the anterior half of the body, (that part which bears the legs, and is the head and thorax of the spider joined together). The eyes vary in number and arrangement in different kinds of spiders, and vary in size on the individual. The common ground or running spiders have eight eyes (which is the more usual number among spiders) and they are arranged as shown in figure 64. Have the children discover which of the eyes are larger than the others. Have the children look for the jaws (mandibles) of the spider. With a pin press the jaws apart laterally and examine one of them carefully. Each jaw (fig. 64) is composed of a firm, smooth, sharp, pointed tip and a thicker hairy basal part. The tip is the fang, which is thrust into the prej^ and the basal part contains the poison sac. From the poison sac the poison runs thru the fang and out of it thru a tiny hole near the point. Ex- •^ Fig. 64. Front amine now the spinning organs. the posterior of head of spider showing: eyes tip of the body may be seen a few small finger-like and mandibles projections, the spinnerets (fig. 65); (some of these are so small and so much concealed by the others that it will be difficult for the children to determine exactly how many there are). From these comes the silk when the spider is "; Each of these little finger- like spinnerets bears on its surface many very small papillae, the spinning tubes. These cannot be seen with the unaided eye, but. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - col
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