the peculiarity which renders it reluctant to under- go malignant change. Fibroma is ihe commonest innocent solid tumour. Malignant disease (carcinoma and sarcoma) may be summarised as follows:— Order SALIENTIA (Ecaudata). OPISTHOCOELA. Families Discoglossidae, Pipidae. ÅNOMOCOELA, Family Pelobatidae. PROCOELA. Families Bufonidae, Hylidae, Brachy- Sub-order 1. NARCOBATOIDEA.—Family Torpedinidae. Sub-order 2, Bartomerea.—Families Rhinobatidae, Raiidae, Trygonidae, Myliobatidae, Mobulidae. NOTIDANOIDEA. Families Chlamydoselachidue, Pristidae,