. Transactions and proceedings of the New Zealand Institute . air being perfect. Twopairs are directives. Gonads.—I saw no reproductive organs in my cross-sections, but ovaappeared on a mesentery in a longitudinal section. They were close up to the sphincter. I was unable to determine to what cycle themesentery belonged. Presum-ably the young of this speciesare retained in the body tillfully formed, for I found onespecimen which had twelveyoung ones attached to the out-side of the body-wall in a regulartransverse circle about one-thirdof the height of the wall fromthe foot. This is shown in fi
. Transactions and proceedings of the New Zealand Institute . air being perfect. Twopairs are directives. Gonads.—I saw no reproductive organs in my cross-sections, but ovaappeared on a mesentery in a longitudinal section. They were close up to the sphincter. I was unable to determine to what cycle themesentery belonged. Presum-ably the young of this speciesare retained in the body tillfully formed, for I found onespecimen which had twelveyoung ones attached to the out-side of the body-wall in a regulartransverse circle about one-thirdof the height of the wall fromthe foot. This is shown in fig. 6of the text, and in Plate XXI,fig. 1. If the young are not re-tained till they are considerablyadvanced, it is difficult to seehow they can become attached in this manner unless there are externalIjrood-pouches. I have seen no evidence in support of the latter view. Acontia.—These are emitted from the mouth readily, but not in greatiuimbers. Dimensioyis.—Height, 12 mm. ; breadth, about the of the Species.—Island Bay, Ohiro Fig. 6. 38-i Transactions. 7. Sagartia vagrans (sp. iiov.). Pedal-disc.—The ectoderm is thick, and presents no unusual mesogloea is much vacuolated, and the endoderm is thin. Column.—The colour is dirty-white and ohve-brown in alternate longi-tudinal lines, or the whole may be dirty-white, or grey, or even pink. Thereis a circular muscle in the wall throughout its entire length carried on regularfolds of the mesogloea. Tentacles.—These are very fine and threadUke. Their colour is salmon-pink, though in specimens they are white. They are of different lengthsin the different cycles. There are several cycles, but the tentacles are sonumerous and crowded that it is impossible to make out how many cyclesthere are. Judging from cross-sections I should say there are four structure the tentacles resemble those of the last species [S. nutrix),but there is a specially well-developed iiervous layer. O
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