The Quarterly Journal of Microscopical Science for March 1895 contains:—On the variation of the tentaculocysts of Aurelia aurita, by Edward T. Browne. (Plate 25.) Of 359 Ephyræ collected in 1893, 22˙6 per cent, were abnormal in possessing more or less than eight tentaculocysts; and of 1156 collected in 1894, nearly the same percentage, 20˙9 was obtained. Of 383 adult Aurelia collected in 1894, 22˙8 per cent, were abnormal.—On the structure of Vermiculus pilosus, by E. S. Goodrich, gives a detailed account of this interesting Oligochæte, found near Weymouth in 1892. (Plates 26ndash;28.)—On the mouth parts of the Cypris stage of Balanus, by Theo. T. Groom. (Plate 29.) “It maybe regarded as tolerably certain that: (1) The antennæ of the Nauplius become definitely lost with the moult resulting in the production of the Cypris stage. (2) The biramous mandibles of the Nauplius become reduced at the same time to the small mandibles, the ramus being probably preserved in the form of the small palp. (3) The first pair of maxillæ arise behind the mandibles, and at a later date, as a small pair of foliaceous appendages. (4) The second pair of maxillæ arise still later, just in front of the first pair of thoracic legs (cirri).”—A study of Coccidia met with in mice, by J. Jackson Clarke. (Plate 30.)—Observations on various Sporozoa, by the same. (Plates 31–33.)—Revision of the genera and species of the Branchiostomidæ, by J. W. Kirkaldy (Plates 34 and 35), enumerates two genera, Branchiostoma (as sub-genera, Amphioxus, Heteropleuron) and Asymmetron. A new species of Heteropleuron, H. cingalense, is described.—On Sedgwick's theory of the embryonic phase of ontogeny as an aid to phylogenitic theory, by E. W. MacBride.