. f il'l 1 M Text-fig. 19. Physalia physalis. Young right-handed specimen, K2, viewed from above, showing the positions of the seven main zone cormidia. Now that I have made a fresh study of Physalia I can in general confirm the facts given by Steche (191 o, p. 361) about the main zone of cormidia in young specimens except that I find seven cormidia. This is the most valuable part of his paper, being an analysis of young specimens collected by' Vettor Pisani' in the Pacific, Indian and Atlantic Oceans. The earlier part of the same paper dealing with still younger developmental stages was based
. f il'l 1 M Text-fig. 19. Physalia physalis. Young right-handed specimen, K2, viewed from above, showing the positions of the seven main zone cormidia. Now that I have made a fresh study of Physalia I can in general confirm the facts given by Steche (191 o, p. 361) about the main zone of cormidia in young specimens except that I find seven cormidia. This is the most valuable part of his paper, being an analysis of young specimens collected by' Vettor Pisani' in the Pacific, Indian and Atlantic Oceans. The earlier part of the same paper dealing with still younger developmental stages was based on deductions made from figures by Huxley and Haeckel. This part, in my view, is not of much value because these figures themselves are not all of sufficient accuracy to be reliable. Haeckel's (1888) figures in particular are obviously simplified, idealized and, in some respects, erroneous as Steche suspected.* There is a further useful criticism I must make of * For instance Haeckel's fig. 3 of a specimen purporting to be about 17 mm. in float-length was probably finished from a wrongly interpreted sketch. It shows a large ampulla at the base of the primary polyp where one never develops. In the original sketch, no doubt this was correctly meant to represent the oral end of the float, but in the finished drawing, a gap has appeared between this end of the float and the oral zone of cormidia which is labelled as a tentacle. The tiny tentacle so characteristic of the primary polyp can just be recognized at its base. It is shown clearly in Haeckel's fig. 4. His fig. 3 does show what might be taken to be five cormidia in the main zone as one would expect, but the gonodendra have been repre- sented as too far advanced in development, and the ampulla of the cormidium at the oral end of the main zone appears to be unusually large. The muscular lamella uniting the ampulla to the base of the tentacle has been omitted, and the extent of the remains of the deflated crest is not properly
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