Page:The Zoologist, 3rd series, vol 2 (1878).djvu/55

Rh place of the absent external branchiæ. He states that the size of the jawchamber is increased by the raising of the "compasses" when the transverse muscles contract, especially if the jaws be protruded. Under such conditions water finds ingress by a crevice produced, and the interiorly-placed gills thus bathed. The peculiar mechanism of the teeth and jaws was here explained, and the function of the so-called "compasses" noted. As regards the "pedicillariæ" of the Cidaridæ, Mr. Stewart observed that when the jaw ends in a terminal fang the chamber has a second opening in addition to the large triangular tooth-armed orifice near the tip, the fang itself being hollow and perforated external to and in front of the tip. He suggests that this probably serves as a channel for the injection of a poison, secreted by two glands placed in the vicinity of the pedicillarian head. He compares this to the falces of the spider or to the poison-fangs of venomous serpents. Another point to which he called attention was that in Cidaris tribuloides and Phyllacanthns bucculora, in addition to the calcareous arches bridging over the ambulacral pores (J. Müller's vertebral processes) there are delicate solid spines between each pair of pores, which project downward and tend to arch over the ambulacral vessel. These spines recal the similar processes scattered over the inner surface of the corona of the Clypeastridæ. He further showed the genital gland of Dorocidaris papillata as possessing a calcareous spicular framework, and that the abundance or paucity of these vary considerably according to circumstances. In Sir Wyville Thomson's lately-described new species of Cidaris (C. nutrix), the latter condition is dwelt on as distinguishing it from D. papillata—a consideration which may hereafter require to be modified.

A short note "On the Migration of Wild Geese," by Dr. R.C.A. Prior, was read, in his absence, by the Secretary, and was to the effect that an immense flock of Wild Geese had lately passed over the Azores, and these were supposed to have come from Newfoundland and to be on their way towards Morocco. He considered that a wide dispersion of the seeds of water-plants would be likely to result from such a migration.

Mr. Charles O. Waterhouse communicated a "Report on a small Collection of Insects obtained by Dr. J.C. Ploem in Java, with a Description of a new Species of Hoplia." These insects had been collected in the vicinity of Sindang-læeja, and transmitted safely to England by post in the hollow of a piece of bamboo. Besides a number of specimens of the new species (Hoplia aurantiaca) there were examples of Popilia biguttata, Wied., Chalcosoma atlas, Linn., Dascyllus fulvulus, Wied., a variety, Rhyparida? sp., and some undetermined species of Gryllus and Forficula.

Several botanical papers were then read, and some exhibitions followed. —