. Annals of the Entomological Society of America. Entomology. 1918] Thoracic Sclerites of Dissosteira 349 (in which the letters "x" are contained in Text figure 2). Whether the angle containing the two letters "x" (Text figure 2) is a right angle, or an acute angle, is a feature used in classi- fication. If the sides of the posterior region of the pronotum instead of making an angle, extend approximately straight across, the pronotum is spoken of as truncate posteriorly. Sim- ilarly, if the anterior margin is approximately straight, it is spoken of as truncate anteriorly. W
. Annals of the Entomological Society of America. Entomology. 1918] Thoracic Sclerites of Dissosteira 349 (in which the letters "x" are contained in Text figure 2). Whether the angle containing the two letters "x" (Text figure 2) is a right angle, or an acute angle, is a feature used in classi- fication. If the sides of the posterior region of the pronotum instead of making an angle, extend approximately straight across, the pronotum is spoken of as truncate posteriorly. Sim- ilarly, if the anterior margin is approximately straight, it is spoken of as truncate anteriorly. Whether the surface of the pronotum is smooth, granulated (powdery appearing), wrinkled, rugose or roughened with numerous tubercles, are other features of value in Fig. 1. Ventral view of prosternum of i?Aowa/ga. Fig. 2. Dorsal view of upper portion of pronotum of Dissosteira. Fig. 3. Vertical transverse section through wall of pronotum of Dissosteira. In the grasshopper Dissosteira, the pronotum is divided by a notch "n" (Fig. 1) and an impressed line "su" extending downward from it, into a front and hind lobe. The dorsal ridge "mc" (Fig. 1 and Text Figs. 1 and 2) extending longitu- dinally along the median line of the pronotum is called the median carina, and in Dissosteira it is broken by a single notch "n" (Fig. 1), while in other grasshoppers there may be two such notches. The median carina "mc" of Fig. 1 is high and arched on the hind lobe of the pronotum of Dissosteira, but in other grasshoppers it may be nearly obsolete on the hind lobe. This, and other features, such as whether the median carina is irregular (as in Dissosteria) or whether it is even in contour, are features used 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 ori
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