Quarterly journal of microscopical science . and edges of theplates can be easily painted with water-colours. The author is indebted to the late Dr. W. G. Ridewood forsuggestions as to reconstruction models, and to Professor PaulPelseneer for information upon the general morphology of theTaenioglossa. 2. Structure. 1. The Alimentary System. The oral cavity (Text-fig. 1) is usually deep and it exhibits a pair of lateral diverticula which aresometimes forked. In general it agrees with that of other ANATOMY OF PALUDESTRINA 161 members of the genus. It is lined by a cuticle which
Quarterly journal of microscopical science . and edges of theplates can be easily painted with water-colours. The author is indebted to the late Dr. W. G. Ridewood forsuggestions as to reconstruction models, and to Professor PaulPelseneer for information upon the general morphology of theTaenioglossa. 2. Structure. 1. The Alimentary System. The oral cavity (Text-fig. 1) is usually deep and it exhibits a pair of lateral diverticula which aresometimes forked. In general it agrees with that of other ANATOMY OF PALUDESTRINA 161 members of the genus. It is lined by a cuticle which is fairlythin ventrally, but becomes thicker dorsally. This cuticle issecreted by a columnar epithelium which is continuous withthat of the lips and adjacent parts. Each cell of this epitheliumcontains an elongate, deeply-staining mass of secretion whichoccupies the major portion of the cell and usually obscuresthe nucleus. These secretion-masses are especially welldeveloped where the cuticle is deepest; and in these areas the Text-fig. Transverse section through the mouth, c, cuticle; m, mandiblesse, secretory epithelium. whole epithelium is characterized by a mass of extra-cellularpigment in the shape of very small, subcircular granules. In the upper portion of the mouth is found a pair of man-dibles. These consist of a number (minimum 18, maximum 2old found inVitrella (20). That the secretion-masses are intimately con-cerned in the formation of these is shown by the fact thaiplates are often continuous with the former. The mandibularplates stain very sharply with eosin, the rest of the cuticlebeing more or less unaffected by the Btain. There i* sometimespresent, in ;uldition to the mandibles, a specialized piece f 162 GUY C. ROBSON cuticle just below the mandibles on each side. There is alsousually a median dorsal projection, dagger-shaped in transversesection. This also stains sharply wi
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