to cystic dilatation without a corresponding multiplication of the cells lining them, many small cysts occur lined by flattened cells forming almost a pavement epithelium. The stroma of this tumour was very abundant and sclerotic, consisting of narrow spindle cells with small FIG. 3.-Grouse: Primary adeno-carcinoma of small intestine. Infiltrative growth in all coats of intestine: great thickening of circular muscular layer, the surface of which at one part forms the base of the ulcer. x. 15 darkly-stained nuclei lying between thick bundles of collagenous fibres. The mode of spread and the relation to the structures of the gut-wall are the same as we have already described in a case of primary To face p. 47.] Microphoto by W. Imboden. FIG. 4.-Fowl: Squamous cell carcinoma of buccal mucous membrane. (From a preparation by Dr. M. Koch.) X 15 FIG. 5.-Canary: Columnar-celled carcinoma. Tumour acini lined by columnar or adeno-carcinoma of the small intestine of the mouse (cf. figs. 40 and 41, Second Scientific Report 1905). Columnar-celled carcinoma of the ovary of Canary. The relatively enormous tumour (3 cm. diameter) distended the abdominal cavity, and was sent to us by Mr. F. W. Cousens, F.R.C.V.S., who informed us that the peritoneum was covered with secondary growths. On section it was pale with yellowish-white nodules scattered throughout. On microscopical examination (fig. 5) the growth shows large necrotic areas, and between these irregular acini very variable in size lined by columnar epithelium. The connective-tissue stroma consists of broad strands of spindle-cells with abundant collagenous fibrils between. But for the presence of nucleated erythrocytes in the blood-vessels one might imagine that the growth was from the ovary of the human subject. REPTILES. Up to the present no malignant new growth has been recorded in reptiles. Pettit (Bull. Mus. Hist. Naturelle, Paris, 1902) has described a fibroma in the stomach of a python. M. Koch demonstrated before the German Pathological Society in 1904, a papilloma of the occipital region of a lizard (Lacerta agilis). AMPHIBIANS. The new growths from Amphibia are still very limited in number. They have, however, a particular interest from the zoological position of this group, and the clearness of the histological pictures due to the large size of the cells of these animals which have remained the classical objects for cytological study, especially with regard to celldivision, ever since Flemming published his epoch-making studies on indirect (mitotic) cell-division in Salamandra in 1882. Eberth described multiple adenomata of the skin of the frog in 1868, Pettit described a fibro-papilloma of the hand in Cryptobranchus japonicus in 1902, and in 1903 Pick described a cystic carcinoma of the testis in the same animal. In 1905 Smallwood described and figured bilateral adrenal tumours in the kidney of the frog, in regard to which some additional points of interest are mentioned below. In 1906 Dr. M. Plehn described a tumour in the ovary of the frog (R. esculenta) which she regards as a multiple carcinoma. The tumours were bilateral, Through the kindness of Mr. Smallwood, of Syracuse University, we have had an opportunity of studying the new growth in a frog's kidney, the naked-eye appearances and histology of which he has described and figured in Anatom. Anzeiger, 1905, fig. 6. To that account it is only necessary to add a short description of the microscopic anatomy of the growth and of its exact relation to the kidney substance. Fig. 7 shows that its structure is that of a columnar-cell carcinoma with extremely elongated slender cells arranged in irregularly shaped acini. Towards the surface of the growth the cells in the younger acini are shorter and almost form a cubical epithelium. Mitotic cell-division is in rapid process throughout thegrowth. The kidney tubules around the growth are compressed and flattened, and there are isolated tubules lying between the tumour acini, and where this is so they are much compressed and distorted, their epithelium showing also distinct granular and fatty degeneration. The expansion of the connective-tissue capsule of the kidney due to the growth of the tumour is accompanied by infiltration of the kidney substance, and, so far as microscopical appearances go, they are conclusive as to the carcinomatous nature of the new growth. Smallwood, reasoning from the position of the growth, concluded that it had arisen from the adrenal bodies, which in the frog lie imbedded in the ventral surface of the kidney substance throughout the whole length of the organ. Histologically the cells do not present the slightest trace of the characteristic granules of the adrenal tissue, and the tumour parenchyma either had arisen from the cortical adrenal tissue or from other epithelial elements of this region. Two cases of carcinoma of the skin have been obtained from the frog. One of these we owe to our former colleague, Dr. Cramer, of the Physiology Department of Edinburgh University. The growth was situated on the inner aspect of the thigh of an adult male frog. It was hemispherical in form, projecting sharply from the surface, and the skin covering it was stretched over its surface. Microscopically the growth consisted of closely packed alveoli of tumour cells arranged in many layers around central spaces either filled with fluid or cellular débris. Delicate connective-tissue septa separate the alveoli from each other and carry capillary vessels moderately distended with blood. Towards the deep surface of the growth isolated alveoli pass for a short distance between the subjacent muscle-fibres (fig. 8, low power). At one part of the surface the tumour parenchyma is seen in anatomical continuity with the covering epithelium (fig. 9), and in places the cells of the tumour parenchyma are connected to one another as well as |