658 SCIENTIFIC AND APPLIED PHARMACOGNOSY 



smooth or somewhat rough from adhering fruit pulp, marked by a 

 shallow groove or slight ridge parallel to and within 1 mm. of the 

 margin; raphe not conspicuous, hilum characterized by a minute 

 depression; seed-coat consisting of two distinct layers the outer 

 white and coriaceous and the inner dark green and membranaceous; 

 embryo white, straight, with a small hypocotyl and two plano-convex 

 cotyledons; slightly odorous when contused; taste bland. 



Inner Structure. The outer epidermal layer consists of palisade- 

 like cells, the outer walls usually being torn off so that it appears as 

 though the seeds were covered with very long hairs; a sub-epidermal 

 layer consisting of 5 to 12 rows of cells having slightly thickened, lig- 

 nified and porous walls; a layer of strongly lignified stone cells, ellip- 

 tical in outline; a single layer of small cells resembling those of the 

 sub-epidermal layer; several rows of spongy parenchyma cells with 

 characteristic reticulate markings and separated from each other by 

 large intercellular spaces; several layers of parenchyma cells, the 

 inner layer being more or less collapsed and having on the inner por- 

 tion a single epidermal layer the cells having rather thick walls; the 

 perisperm cells are usually more or less collapsed; the endosperm 

 consists of a single layer of cells filled with small aleurone grains ; the 

 cotyledons consist of thin-walled, isodiametric, elongated, or palisade- 

 like cells containing a fixed oil and numerous small aleurone grains. 



Powder. Yellowish-white; starch grains few, spheroidal from 

 0.002 to 0.004 mm. in diameter and occurring in the cells of the outer 

 epidermis and endosperm; characteristic, ellipsoidal, lignified, porous, 

 thick-walled stone cells, from 0.045 to 0.100 mm. in diameter; yellow 

 pigment cells of seed-coat ; oil and protein grains in embryo. 



Constituents. Fixed oil about 40 per cent; starch about 30 per 

 cent; proteins; a resin. There is no indication of the presence of any 

 principle possessing anthelmintic properties. Any therapeutic value 

 must be attributed solely to mechanical action of the sharp edges of 

 the bruised seeds. 



Allied Plants. The seeds of other species of Cucurbita are 

 also used in medicine; in Italy C. maxima and in the West Indies 

 C. occidentalis are the sources of the drug. 



The seeds of other members of the Cucurbitaceae are also employed 

 in medicine; they include the seeds of watermelon (Citrullus vulgaris), 

 cucumber (Cucumis sativus), muskmelon (Cucumis melo) and lagen- 

 aria (Cucurbita Lagenaria). 



Watermelon seeds contain a fixed oil resembling in composition 

 that obtained from pumpkin seed. It also contains a resin which 

 consists in part of a crystalline compound, cucurbitol. 



