. The Australian zoologist. Zoology; Zoology; Zoology. FRASER. 129 these are developed a varying number of convex anal veins, of which the first two at least (Al and A2) are separated by a concave intercalated vein, the inter-anal, AxP Fig. 2.—Odonatoid type of wing; base only shown. AxP. Axillary plate. (2) The Odonatoid type, in which the weakly chitinized plates found in the older Plectopteroid types are replaced by a single stoutly chitinized axillary plate (AxP in Fig. 2) to which are attached all the posterior veins of the wing, viz., the Radius, Media, Cubitus and Anal. (3) The Ne
. The Australian zoologist. Zoology; Zoology; Zoology. FRASER. 129 these are developed a varying number of convex anal veins, of which the first two at least (Al and A2) are separated by a concave intercalated vein, the inter-anal, AxP Fig. 2.—Odonatoid type of wing; base only shown. AxP. Axillary plate. (2) The Odonatoid type, in which the weakly chitinized plates found in the older Plectopteroid types are replaced by a single stoutly chitinized axillary plate (AxP in Fig. 2) to which are attached all the posterior veins of the wing, viz., the Radius, Media, Cubitus and Anal. (3) The Neopteroid type, in which the original series of weakly chitin- ized plates found in the Plectopteroid type is replaced by a set of three strongly chitinized and distinct axiliaries, (lAx, 2Ax and 3Ax). The whole of the anal veins in the Neoptera appear to have been evolved in intimate relationship with the third axillary (3Ax), and all the anal veins present are always convex veins. From a study of fossil I am of opinion that there are only two anal veins originally in the Neoptera, viz., 1A and 2A (or, if preferred, Al and A2). The so-called third anal (3A) of Comstock can be clearly seen in such ancient Orders as Protoperlaria, to be nothing else than a posterior convex branch of 2A. If, therefore, we continue to use the notation 3A, we must always remember that it is only for convenience and that this vein, and 4A when present, are only branches of the second anal vein. Reviewing the above evidence, we see that the most ancient type of. 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 Royal Zoological Society of New South Wales; Royal Zoological Society of New South Wales. Proceedings. [Sydney, Royal Zoological Society of New South Wales]
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectzoology, bookyear1914
