Plate I. 



Page 



Fig. I. Pachyckalina Schimdtii ii. sp. '/i 5 



— 2. Pachyckalina Schmidtii u. sp. '/i — 



— 3. Siphonochalina pulcherrinia Frstdt. '/i 13 



— 4. Siphonochalina pulcherrima Frstdt. A tube cut through, '/i — 



— 5. Halichondria velamentosa Arm. Hans. A calicular specimen; the skin wanting 



in some places, '/i 22 



— 6. Reniera iirceolus Rathke et Vahl. '/i 35 



