MACROSCOPIC AND MICROSCOPIC CHARACTERS OF PLANTS. 



831 



parent, and intermediate in width between the parents, 

 but nearer C. insigne maulei. 



Both pointed and club-shaped hairs are present at 

 the top of the flower-stalk. Equal numbers of pointed 

 and club-shaped hairs are present in C. villosum; 2 

 pointed to 1 club-shaped in C. insigne maulei; and in the 

 hybrid almost exactly mid-intermediate in proportions 

 between those of the parents. There are 3 hairs in a field 

 in C. villosum, 5.1 in C. insigne maulei, and 4 in C. 

 nitens. The pointed hairs are longer in C. villosum than 

 in C. insigne maulei, and in the hybrid between those 

 of the parents in length, but nearer C. insigne maulei 

 than C. villosum. The club-shaped hairs are longer in 

 C. villosum than in C. insigne maulei, and in the liybrid 

 very nearly identical with those of C. villosum. (Table 

 J 60.) 



The color at the top of the flower-stalk in C. villosum 

 is green, with many purple and colorless hairs, due to 

 some cells containing green plastids and to others with 

 a violet sap and yellow chromoplasts. The hairs all 

 contain yellow chromoplasts which become orange-brown 

 in the end cells. Nearly all of the hairs contain a deep- 

 violet sap. In C. insigne maulei the color is purple, with 

 many hairs, due to all the cells (except those from which 

 hairs arise) being filled with deep-violet cell sap. Yellow 

 chromoplasts appear to be present in these cells. The 

 hairs are filled with violet sap, so deep in color as to 

 appear almost black; yellow-orange and orange-brown 

 chromoplasts are present especially in the end cells. In 

 the hybrid the color both macroscopically and microscopi- 

 cally is very nearly the same as in C. villosum. 



The epidermis at the middle of the flower-stalk con- 

 sists of thin, lateral-walled, rectangular cells having a 

 thick outer cuticle. They are larger in C. villosum than 

 in C. insigne maulei, and are shorter and wider in the 

 hybrid than in either parent. (Table J 60.) 



Hairs similar to those at the top of the flower-stalk 

 are present at the; middle. Pointed hairs are twice as 

 numerous as the club-shaped in both C. villosum and 

 C. insigne maulei, but are a little more numerous than the 

 club-shaped ones in the hybrid than in either parent. 

 The hairs in a field number 3.1 in C. villosum, 5.2 in 

 C. insigne maulei, and 4.8 in C. nitens. The pointed 

 hairs are longer in C. villosum than in C. insigne maulei, 

 and in the hybrid between those of the parents but 

 nearer those of C. insigne maulei. The club-shaped hairs 

 also are longer in C. villosum than in C. insigne maulei, 

 but are shorter in the hybrid than in either parent. 

 (Table J 60.) 



The color is the same at both middle and top of the 

 flower-stalk. 



Transverse sections of the flower-stalk were made at a 

 point midway between the top and the base. Outermost 

 is a layer of rounded epidermal cells with slightly thick- 

 ened inner and lateral walls, and with a greatly thickened 

 outer wall. The outer wall is ridged in all three plants, 

 but is not as thick in C. villosum as in C. insigne maulei. 

 In the hybrid the thickness is identical with that of C. 

 insigne maulei. From this layer the hairs arise. The 

 cells themselves are larger in C. villosum than in C. in- 

 signe maulei, and between those of the parents in size in 

 the hybrid, the depth being nearer C. villosum and the 

 width mid-intermediate. (Table J 60.) 



Beneath the epidermis is a zone of cortex, consisting 

 of several layers of rounded, thin-walled, chloroplast- 

 containing cells, the outer layer of which is thicker- 

 walled. There are 10 to 12 layers in C. villosum, and 

 9 to 10 in C. insigne maulei and in the hybrid. The 

 cortex is much wider in ('. villosum than in ('. insigne 

 maulei; and between the parents in width in tin- hybrid, 

 but much nearer C. insigne maulei. (Table J 60.) 



Flower. 



Sections of the upper epidermis of the dorsal sepals 

 of the three plants were made at the median [mint along 

 the midrib. The upper epidermal cells are wavy-walled, 

 and are smaller in C. villosum than in C. insigne maulei, 

 and larger in the hybrid than in either parent. No hairs 

 are present on the upper epidermis. (Table J 61.) 



The color of this region is pea-green, with dark- 

 brown veining in C. villosum; light green with dull 

 brownish-purple spots in C. insigne maulei; and a darker 

 green with darker brownish-purple spots in the hybrid. 

 It is due in C. villosum to the presence of green plastids 

 in the upper epidermal cells, and to a red-violet cell sap 

 in the layer beneath ; in C. insigne maulei to yellow-green 

 plastids in the upper epidermal cells and a red-violet 

 sap (at the region of the spots) in the layer beneath; 

 in the hybrid, to yellowish-green plastids in the upper 

 epidermal cells and to red-violet cell sap (over the spots) 

 in the layer beneath, the color being slightly deeper than 

 that of C. insigne maulei. Above the green area in C. 

 insigne 7)iaulei and in the hybrid yellowish-green plastids 

 only are present. 



Sections of the lower epidermis were taken along the 

 midrib at the middle of the dorsal sepal. Hairs, both the 

 pointed and the club-shaped, are very numerous. The 

 club-shaped hairs are relatively more numerous (1 to 4) 

 in C. villosum, but the pointed hairs are relatively more 

 numerous (7 to 1) in C. insigne maulei; both are present 

 in practically the same numbers in the hybrid. The 

 pointed hairs are very much longer in C. villosum than in 



