Development of Cassytha filiformis, L. 405 



cells, with scattered intercellular spaces. Each cotyledon 

 is directly inserted into the radicle, which is entirely com- 

 posed at this time of undifferentiated tissue. At the point 

 of insertion some of the cells are a little elongated, and 

 spread in four or five bundle-like traces from the radicle into 

 the cotyledons, as is shown in Fig. 3. The two cotyledons 

 are not, however, exactly opposite in insertion, hence the 

 appearance of distinctness shown in the figure. 



Both the cotyledons and the radicle are richly laden with 

 ellipsoidal starch grains, protein material and less abundant 

 globules of yellow oil. 



Throughout the entire plant the starch is remarkably 

 abundant and difficultly soluble. Continued boiling of thin 

 sections with taka-diastase is the only means by which it 

 can be satisfactorily removed. This is in all probability due 

 to the superabundance even in the cotyledons of a thick 

 mucilaginous material which cannot be localized in special 

 cells, but which seems to be everywhere present. It swells 

 and becomes very troublesome in weak alcohol, but is not 

 dissolved by it, nor by soaking and boiling in water or KOH. 

 Alcoholic material after a few months becomes somewhat 

 granular, as if from coagulation of the mucilage, but when 

 manipulated in weaker alcohol it swells and is as evident as 

 before. It is not so stringy in fresh specimens as in alcoholic 

 material. 



There is no albumen ; some starch is present in the middle 

 layer of the receptacular tube, but this is a natural accom- 

 paniment of the chlorophyll present here, and cannot reach 

 the embryo, owing to its isolation. 



2. Seed Germination. — Hitherto the germination and 

 seedling growth of this plant have not been studied. The 

 germination of seeds was most successful in the two stove- 

 houses of the Botanic Garden, at a temperature ranging from 

 88° to 90° F. The humidity was rather high, but it was 

 found advisable to keep the soil fairly dry, as a constantly 

 damp soil caused the formation of a white fungoid bloom 



