Monotropaceae with Reference to Ericaceae 67 



Thesium of the Santalaceae; Cassytha of the Lauraceae; Sali- 

 cornia, Casuarina, Staphylea pinnata. The first three groups 

 are all, with the exception of Nuytsia, parasitic, so that the 

 presence of transverse stomata on the stem may indicate an 

 abnormal system of nutrition. 



In C. maculata the epidermis is almost exactly similar to that 

 of C. umbellata, except that the papillae seem slightly longer 

 and have somewhat thicker walls. 



In P. rotundifolia the epidermal cells are longer and thinner 

 walled; there are no papillae; stomata are more numerous and 

 are mostly of the longitudinal slit type. 



The epidermis of P. elliptica is similar to that of P. rotundi- 

 folia, except that stomata are very rare and in all pieces of 

 epidermis examined were of the longitudinal type. 



In Moneses uniflora there are papillae present as in Chima- 

 phila. The epidermal cells are long, narrow, and thin-walled, 

 and contain chloroplasts as in the preceding. In all the mate- 

 rial examined the writer found no stomata present. 



In Sar codes sanguinea the epidermal cells are also long, nar- 

 row, and thin-walled. Oliver states that no stomata are present 

 on the flower stalk (the ascending axis), but the writer finds 

 that, though rare and somewhat distorted, stomata are un- 

 doubtedly present. Simple stomata with a longitudinal slit as 

 in M. hypopitys (Fig. 4, 4) occur. Others have the guard cells 

 twisted around so that the slit is diagonal (Fig. 4, 2). Others 

 are remarkable in that they have three guard cells (Fig. 4, 3). 

 At the base of the axis a few glandular hairs are present. These 

 increase in number toward the top of the flower stalk. They 

 are multicellular with a thick stalk and a slightly rounded head. 



In Pterospora andromedea the epidermal cells are similar to 

 those of Sarcodes. This is the only member of the Monotro- 

 paceae up to the present that has been described as possessing 

 stomata on the flower stalks. MacDougal (48), p. 38, states 

 "Pterospora is the only dicotyledonous plant without chloro- 

 phyll beside Cotylanthera that is furnished with stomata." 

 These stomata are of the normal type with the slit parallel 

 to the longitudinal axis. They are very rare. Hairs of two 

 types occur on the flowerstalk; simple uniseriate hairs com- 

 posed of 3-4 elongated cells the last one club-shaped ; glandular 

 hairs with a multicellular stalk and a multicellular club-shaped 

 head. 



