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Show 1874.] DR. T. S. COBBOLD ON NEW OR RARE ENTOZOA. 127 had been laid open that I found any visible traces of parasitic disease. From the lower opening of the crop downwards to the termination of the small intestine the canal was more or less crowded with nematode entozoa, all of them being referable to the above-named species. In spite of this state of things, and notwithstanding, also, that the small intestine was inflamed throughout (showing several large ulcerated patches, which here and there measured fully an inch in length), the body of the pigeon exhibited no traces of emaciation. From this it was evident that the parasites had developed rapidly, and that the malady had a correspondingly rapid formation. The local distribution of the parasites themselves was especially noteworthy. One specimen, two inches long, extended from the crop to the proventri-culus. The cavity of this latter organ and also that of the gizzard were crammed with worms, which completely blocked the passage between the two. Three of the worms had also placed themselves within the pyloric opening, their bodies partly lodging within the upper part of the duodenum. The duodenum itself was crowded with these Ascarides ; but their numbers somewhat decreased towards the lower folds of the small intestine. I removed 36 worms from the oesophagus, proventriculus, and stomach, besides 166 others from the intestinal canal, thus obtaining a total of no less than 202 nematodes from this solitary avian bearer. Considering the comparatively large size of these entozoa, this high degree of infection must be pronounced remarkable. The largest female worms measured 2\ inches in length. One of the most interesting facts- serving to exemplify a well-known habit of lumbricoid worms generally- consisted in the circumstance that two of the parasites had succeeded in perforating the horny lining membrane of the gizzard. The injuries had evidently been accomplished during the life of the host, since the walls of the gizzard were inflamed opposite the perforations made by the heads of the parasites. There was a little half-digested and green food within the stomach, the debris of which, when placed under the microscope, showed several characteristic nematode ova. There were no free embryos anywhere discernible ; neither had the development of the freed eggs proceeded beyond the coarsely granular stage of yolk-segmentation. Free eggs were also found both in the small and large intestine. The eggs measured about Y$-Q inch by y^-g- inch in diameter (fig. 7). A n admirable description of the adult parasite has been given by Dujardin; but since the published figures of Rudolphi, Goeze, and Bremser are incomplete, I have thought it desirable to supplement them with others. Thus fig. 8 gives a magnified view of the head of a small female Ascaris maculosa, and shows especially the crenulations or transverse striae on the ala or lateral membranous appendages. These are veritable annulations, or fine circular striae, and not merely contractions of the integument as some have supposed. Dujardin speaks of the alas as scarcely visible; but I always found them more or less well marked and semielliptic in shape, as Rudolphi originally described them. Another sketch (fig. 9) shows an enlarged view of the tail of the male; and, on the whole, this representation agrees |