Scientific Proceedings (54). 



vesicles. The optic stalks, however, and later the optic nerves 

 following the stalks as paths always lead back to the point of 

 their median origin and the optic cross or chiasma is in the median 

 plane, below and outside the brain tissue. The attainment of this 

 position of the optic cross would seem mechanically impossible 

 if the eyes arose from lateral medullary tissues since the optic 

 fibers following the stalks would enter the brain laterally and would 

 necessarily cross within the brain tissue, not below and outside as 

 the nerves actually do. 



There is no medullary tissue other than future eye tissue be- 

 tween the eye anlagen, therefore, Spemann and others are incorrect 

 in assuming that cyclopia is due to a failure to develop of tissues 

 between the eyes thus permitting the eye anlagen to slump towards 

 the median plane and fuse. The defect is due to a failure or 

 arrest in development of the eye material itself. 



102 (798) 



The occurrence of betaine in the muscles of invertebrates. 



By D. Wright Wilson. 



[From the Sheffield Laboratory of Physiological Chemistry, Yale 



University.] 



Betaine, or trimethylglycocoll, was isolated from the muscle 

 tissue of two varieties of mollusc, Pecten irradians, the common 

 scallop, and Sycotypus canaliculars, the periwinkle. 



The tissues used were the adductor muscle of the Pecten and 

 the large pedal muscle of the Sycotypus. The manner of treat- 

 ment was the same in both cases. The muscles were finely 

 ground, extracted with several changes of water and the concen- 

 trated extract freed of colloidal material by precipitation with 

 alcohol and by the regular Kutscher manipulation with tannin. 

 The portion precipitated by phosphotungstic acid was fractioned 

 by precipitation with silver nitrate and barium hydroxide and 

 from the resulting filtrate, betaine was crystallized as the free 

 base and hydrochloride. In both cases, the compound was 

 identified by the melting points of the hydrochloride, picrate and 

 chloroplatinate and by the analyses of the hydrochloride and 

 chloroplatinate. 



