. Elementary studies in insect life. Insects. 266 ELEMENTARY STUDIES IN INSECT LIKE means of flight, they are commonly called the wings. (Fig. 202.) THE ABDOMEN. Among writers upon this subject there exists a differ- ence of opinion concerning the number of segments com- posing the abdomen. It will be evident to the observer here, upon a careful examination, that there are eight segments on the dorsal aspect of the abdomen of the female, and nine clearly shown on the same portion of the male. As will be seen from Fig. 202, we have con- sidered the .segments caudad of segment eight in the femal
. Elementary studies in insect life. Insects. 266 ELEMENTARY STUDIES IN INSECT LIKE means of flight, they are commonly called the wings. (Fig. 202.) THE ABDOMEN. Among writers upon this subject there exists a differ- ence of opinion concerning the number of segments com- posing the abdomen. It will be evident to the observer here, upon a careful examination, that there are eight segments on the dorsal aspect of the abdomen of the female, and nine clearly shown on the same portion of the male. As will be seen from Fig. 202, we have con- sidered the .segments caudad of segment eight in the female, and segment nine in the male, as parts of the dorsal portion, and have numbered them accordingly. The First Segment- - The ventral portion of this seg- ment is dovetailed into the metasternum, and by some authors has been considered a part of the metasternum. The ventral portion is widely separated from the lateral portion of the same segment, by the insertion of the hind leg. The Auditory Organs. - - Just dorsad of the leg in this seg- ment is to be found on each side an oystershell-shaped open- ing, covered by a membrane. These are the organs of hearing, or auditory organs, and the mem- brane covering them is the tym- panum. Second to Eighth Segments— The second to the eighth seg-. FIG. -203. Exterior view of auditory organ. Sp, spiracle. Clear space is tympanum. Small dark body in center is vesicle, which is connected by vein to ganglion shown at right. Enlarged fifteen times. ments are each ring-like in 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 Hunter, Samuel John, 1866-1946. Topeka, Kan. , Crane & company
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectinsects, bookyear1902
