[Ball cells and the structure of the epidermis of anuran larvae. I. Ascaphus truei Stejneger]. / Uber Kugelzellen und die Struktur der larvalen Epidermis von Froschlurchen. I. Ascaphus truei Stejneger

1. A special cell numerously occuring in the epidermis of the anuran larva of Ascaphus truei which must be called ball cell because of its usual shape, more thoroughly has been investigated by microscope. Especially plain preparations besides cross sections stained in customary way, respectively worked up histochemically with regard to orientation, were used for that. 2. The ball cell-the very characteristical epidermal attribute of Ascaphus larva-is an exocrine element with apparently far extending continuous merocrine secretion. The product contains mucous substances partly being of acid kind. The activity in any case is extending to metamorphosis. 3. Altogether the cells are forming a simple endoepidermal plain gland with differently displayed parts: strong condensation of the elements, for instance, in a circumoral zone, scanty distribution in the whole middle back over all.