群体ホヤ内の個虫の配置と方向について

概要

論文の詳細を見る
From the structural organization, ascidian colonies are divided into four different types. Polycitor proliferus forms a colony without both common vascular system and common cloaca. Aplidium yamazii possesses common cloaca, while does not common vascular system. In Symplegma reptans, common vascular system is present, while common cloaca is absent. In Botryllus scholsseri, common vascular system and common cloaca are both present. Orientation of zooids and distances between two adjacent branchial apertures were compared among these four colonies. Zooids are arranged along about the same direction in P. proliferus and S. reptans, and radially among the common cloacal unit in A. yamazii and B. schlosseri. The distances between two adjacent branchial apertures are approximately constant, although they differ from species. The distance per size of zooid in P. proliferus is longer than that in A. yamazii, and that in S. repatans is longer that in B. schlosseri. In a similar manner, that in P. proliferus is longer than that in S. reptans, and that in A. yamazii is longer than that in B. schlosseri. Formation of common vascular system or common cloaca may shorten the distance between two adjacent branchial apertures, therefore, it may increase the number of zooids per same area of the colony.
横浜国立大学の論文
1993-03-27