COMPARATIVE ANATOMY OF THE CUCURBITACE.E. 49 



The cuticle on the epidermis is mostly thin, except in Citvullus 

 vuhjnrh, IrlcIiosaiUhes cucumeroides, T. Japon ica nnd T. mulliloha, 

 where it is much thickened. 



The thick-walled, irregular, pitted cells constituting the second 

 layer of the testa have some intercellular spaces, and often attain 

 a great thickness in, Adinostemyna racemosum, Schizopepo7i hryonke- 

 folius, var. japon icus, JTomordica Charanlia, Citndhis vulgaris, 

 Ben'tncasa cerifera, Lagcnaria vulgari>^, Trichosanihex cucumcr aides, 

 T. jap oui ca and T. iimltiloha. 



In Melolhria japonica, Luffa cylindrica, L. acutangida, 

 Cucumis saiiviis, C. Jlelo, Cucurhiia Pepo and Gyiiuioslemiita 

 cissoides this layer occupies a comparatively small portion of the 

 testa. That of Cœurbiéa Pepo^' and Gymiiostemina cissoides is 

 composed of thin-walled cells, furnished with reticulate thicken- 

 ings. In some cases the second layer passes over gradationally 

 to the third layer. 



The stone-cells of the third layer of the testa are especially 

 large, and polyhedral or roundish. They are characterized by 

 the considerable thickness of their walls, and by the presence of 

 a greatly reduced cavity as well as numerous branched pore- 

 canals. This \i\yQY is made up of one or more rows of cells, 

 which sometimes have small intercellular spaces. In Luffa 

 cylindricrr' and X. ac alang ulci'^ it consists of rather large prismatic 

 stone-cells (200 !'■ long and 37 !'■ wide), w'hich are placed radially 

 parallel ; while in Gymnosteinma cissoides it is made up of large 

 reticulate cells. 



The parenchymatous cells of the fourth layer are thin-walled 



1) H. A. LoTAR. loc. cit. p. 213. 



2) Ditto, p. 221. 



3) A. Yasuda. On t!ie Anatomy of L^iffa ar>ila)ir/>ila (L.) Rnxli. R(it;inical M:iQ;nzine, 

 Tokyo. 180G. vol. x. No. 108. p. 37. 



