Anomalous Pupil Reactions.

comment. that histologically the majority of glioma retinae -appear to originate in the inner nuclea layer, a few in the ganglion cell and nerve fibre. layer. They discuss the formation of rosettes as attempts at partial differentiation. to a form imitating more or less closely the primitive epithelium of the neural tube rather than the highly specialized rod and cone cells. For what it is worth they agree that rosettes 'are sometimes found in metastatic 'growths and in medullo-blastomas of the cetitral nervous system and in neuro-blastomnas of the sympathetic nervous system. The authors describe pseudo-rosettes which are aggregations of compressed. glioma cells arranged around a blood. vessel and sometimes bordering a clear space. They classify glioma retinae into three types based on cytology,the degree of undifferentiation of t4e cells and thus the grade of malignancy. These are (l) Retino-blastoma, highly undifferentiated; (2) Neuro-epithelioma, showing slight or partial differentiation as indicated by rosettes or pseudo-rosettes. (3) Astrocytoma, well differentiated neoplasms. Rare in the retina. The cells'.nearly resemble normal astrocytes. The authors comment on the serious prognosis of the retino-blastoma type but in a large proportion of these cases described by them the -opfic nerve and extra-ocular tissues had already been invaded. H. B. STALLARD.