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MR. N. H. POOLE (NATURE, vol. xxiv. p. 485) is apparently right in anticipating that he has discovered either a new habitat for Trichodina pediculis or a new representative of that infusorial genus. Although hitherto regarded as a parasite only of the fresh-water polypes, Hydra vulgaris and H. viridis, I have recently obtained specimens of the type in question living as a parasite, or rather a commensal, on the branchial appendages of the larva of the common newt, Triton cristatus. An allied, but marine species, Trichodina scorpaena, has been recently described by Prof. Ch. Robin, that infests in a similar manner the branchia of fishes belonging to the genera Trigla and Scorpaena, and a further search will no doubt reveal a yet more extensive distribution of the Urceolariidae, including Trichodina, among the Piscine race. Mr. Poole will find full particulars of the data here referred to, together with an account and illustrations of all the forms so far relegated to this somewhat remarkable infusorial group, in Part V., p. 645 et seq., of my “Manual of the Infusoria”, just published.

THE California scorpionfish, Scorpaena guttata Girard, spawns throughout the summer months in aquaria at Scripps Institution. Captive specimens have supplied material for studies on the eggs and early larval stages of this marine species by Barnhart (1932) and David (1939), as well as for the present paper. In the work reported here, the embryonic and prolarval stages are re-described in greater detail in an effort to simplify future comparison with the early pelagic stages of other scorpaenid fishes of the Pacific coast. The eggs and newly hatched larvae from Cortez Banks that Eigenmann (1892) tentatively identified as Fierasfer dubius are here referred to Scorpaena sp. In addition, the literature on early stages of several extra-limital forms of Scorpaena and of certain other fishes is discussed briefly, and the need for more extensive study of developmental characters of scorpaenid fishes is pointed out. The description of S. guttata is based on living specimens except where otherwise stated. This paper is No. 777 in "Contributions from the Scripps Institution of Oceanography, New Series."

Three immature didymozoids are reported from fishes of Palawan Island, Philippines: Torticaecum nipponicum Yamaguti, 1942, from Eleotris fusca; Immature Didymozoid A from Puntius binotatus; and Immature Didymozoid B from Euthynnus yaito. A review of didymozoids listed as Distomum fenestratum Linton, 1907, in the U. S. National Museum Helminthological Collection resulted in their separation into two district forms: D. fenestratum from Gymnothorax moringa, Haemulon plumieri, H. sciurus, H. parra, Remora remora, Scorpaena sp., and Pseudupeneus maculatus; and Immature Didymozoid C from Brevoortia tyrannus, Ammodytes americanus, and Etrumeus sadina. Bucephaloides sibi (Yamaguti, 1940) Hopkins, 1954 (Bucephalidae) is reported from Euthynnus yaito; and Pelorohelmins palawanensis gen. n., sp. n. (Hemiuroidea) from Gazza minuta is described. A new subfamily, Pelorohelminthinae, is created for the latter genus and appears to be most closely related to the family Isoparorchiidae. (Author)