824 



MACROSCOPIC AND MICROSCOPIC CHARACTERS OF PLANTS. 



and a few yellow chromoplasts may be present in both 

 the pointed and the club-shaped hairs. Some of the 

 pointed hairs contain only yellowish chromoplasts, and 

 some of the club-shaped hairs have yellow orange plastids 

 massed in the end-cell. Those containing violet sap are 

 not as numerous in C. lathamianum inversum as in C. 

 lathamianum. 



Sections of the upper epidermis of the lateral petals 

 along the mid-line and at a point equidistant from the 

 base and the apex were examined. The upper epidermal 

 cells have thin, wavy walls, and are a little shorter 

 and wider in C. spicerianum than in C. villosum. In 

 both hybrids the average length is greater than in either 

 parent. The width in C. lathamianum is greater than in 

 either parent; that of C. lathamianum inversum is be- 

 tween those of the parent, but much nearer that of 

 C. spicerianum. (Table J 55.) 



The color is dark green with red-purple midrib in 

 C. spicerianum, and is due to cells filled with greenish- 

 yellow plastids, and at the red-purple line to a deep red- 

 violet sap that fills the cells of the layer beneath. In 

 C. villosum the color above the midrib is deep red-brown, 

 due to yellow chromoplasts in the upper epidermal cells 

 and a red-violet sap in the layer beneath. The red- 

 brown midrib in C. lathamianum and C. lathamianum in- 

 versum is also due to greenish-yellow chromoplasts in the 

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

 of the layer beneath. The only difference between the 

 coloring of the hybrids is that the red-purple midrib 

 line is broader in C. lathamianum inversum than in C. 

 lathamianum. 



The lower epidermis of the petals along the mid-line 

 and at a point equidistant from the base and the apex 

 consists of thin-walled, almost hexagonal cells with only 

 very slightly wavy walls in C. spicerianum; of cells of 

 more irregular shape and with wavy walls in C. villosum; 

 and of cells with irregular wavy walls which appear very 

 much like those of C. villosum in the hybrids. The cells 

 are shorter and broader in C. spicerianum than in C. 

 villosum, and are longer and broader than in either 

 parent. (Table J 55.) 



A few hairs are present on the lower epidermis along 

 the midrib. Sections of the upper epidermis of the petal 

 at the anterior part at the base show long pointed hairs. 

 These hairs are shorter in C. spicerianum than in C. vil- 

 losum and are longer in both hybrids than in either 

 parent. (Table J 55.) 



The color of this portion of the petal is green with 

 reddish-brown specks and violet hairs in C. spicerianum, 

 and is due to pale yellowish chromoplasts in both upper 

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

 some cells and some hairs. The color in the hairs par- 

 tially obscures pale-yellow chromoplasts. Other hairs 

 without the red-violet sap contain deeper yellow-orange 

 chromoplasts. In C. villosum the color is greenish-yel- 

 low with violet hairs and pale brown-purple specks, and 

 is due to a few pale-yellow chromoplasts in the upper 

 epidermal cells and hairs, and to a red-violet cell sap 

 in the hairs and in a few of the cells in the layer beneath 

 the epidermis. In C. lathamianum the color is more 

 greenish than in C. villosum; in C. lathamianum inver- 

 sum more yellowish than in C. villosum, both with brown- 

 purple specks and violet hairs due to yellow chromoplasts 

 in the upper epidermal layer and in the hairs, these 



chromoplasts being obscured by the violet sap. Violet 

 sap is also present in several areas of cells of the layer 

 beneath the upper epidermis where the brown-purple 

 specks are present. 



Sections of the upper epidermis of the labellum were 

 taken at the base along the mid-line. The epidermal cells 

 are somewhat irregular in shape and have thin, wavy 

 walls. They are smaller in C. spicerianum than in C. 

 villosum. The relationship in the hybrids to the parents 

 is very irregular: In length the cells of C. lathamianum 

 are between those of the parents, but nearer C. spiceri- 

 anum, while in C. lathamianum inversum they are longer 

 than in either parent. In width, the cells of C. lathami- 

 anum exceed the widths of those of either parent; but 

 the width in C. lathamianum inversum is less than in 

 either parent. (Table J 55.) 



Long pointed hairs are numerous. They are shorter 

 in C. spicerianum than in C. villosum; shorter in C. 

 lathamianum than in either parent; and between the 

 parents in C. lathamianum, but very near that of C. 

 villosum. (Table J 55.) 



The color of this area in C. spicerianum is green with 

 purple specks and hairs. This is due to the presence 

 of yellowish-green chromoplasts in most of the cells, a 

 red-violet sap in a few cells, and a red-violet sap and 

 yellowish chromoplasts in the hairs. In C. villosum the 

 color is pale yellow, with purple hairs, and with red- 

 purple dots over the veins. This is due to the upper 

 epidermal cells containing a few yellow chromoplasts, 

 to a deep-violet sap in many cells grouped together, and 

 to the short hairs containing yellow chromoplasts and 

 the hairs containing a red-violet sap and yellow chromo- 

 plasts. In C. lathamianum the same area is greenish 

 yellow with deeper and larger dots than in C. villosum, 

 and with purple hairs. Microscopically, the appearance 

 is very similar to that of C. villosum except that the 

 areas of the colored cells are more numerous and the 

 red-violet is of a deeper shade. In C. lathamianum 

 inversum the area is of a deeper yellow than in C. vil- 

 losum, also with purple specks and hairs. Microscopi- 

 cally this also is very similar to that of 0. villosum, 

 but the colored areas are not as numerous, nor is the 

 red-violet sap of so deep a shade. 



Sections of the upper epidermis of the labellum at the 

 most anterior part along the mid-line were examined in 

 the four plants. The upper epidermal cells are very 

 wavy-walled. They are of almost the same length but 

 wider in C. spicerianum than in C. villosum. In length, 

 the cells of both hybrids are greater than in either parent; 

 in width, those of C. lathamianum are between those of 

 the parents, though much nearer to C. spicerianum; that 

 of C. lathamianum inversum, however, is greater than in 

 either parent. (Table J 55.) 



Long hairs, having the last two cells a little shortened 

 and the last cell rounded so as to resemble somewhat 

 the club-shaped hair, are numerous on this area. They 

 are longer in C. spicerianum than in C. villosum. They 

 are shorter in C. lathamianum than in either parent; 

 they are between the two parents in C. lathamianum, 

 but much nearer those of C. spicerianum than C. vil- 

 losum. (Table J 55.) 



The color is brownish purple- in C. spicerianum, and 

 is due to many cells being filled with a pale or deep red- 

 violet cell sap and yellow chromoplasts, to some cells 



