1889.] BOTANICAL GAZETTE. 67 



Fibres and raphides in fruit of Monstera. 



W. S. WINDLE 



(WITH PLATE X.) 



Monster 



ica, belonging to the Aroide*e, and closely related to the 

 Calla. It possesses a weak, elongated, stoloniferous stem, 

 by which it clings to rough walls, or rocks, or firmly clutches 

 some tree by means of its numerous adventitious roots, 

 reaching sometimes 10 to 50 feet in length or more. Jts 

 large, wide-spreading leaves, borne upon long petioles, 

 are perforated by large elongated openings. The cylin 

 drical fruit is an aggregate, termed by Dr. Masters a berry 

 or sarcocarp. It is borne erect upon a long, rounded 

 peduncle among the upper leaves of the plant, and when 

 young is sheathed by a hood-like deciduous spa the. The 

 fruit when mature is about 20 cm. in length by 4 cm. in 

 diameter. Running through its center is a thick core (en- 

 docarp), surrounding which is the pulpy, edible portion. 

 This latter part is composed of small, elongated, hexagonal 

 segments placed side by side. Each is made up of a thick 

 inner part (mesocarp), and of a thinner outer part (exocarp). 

 These separate from each other in the ripened fruit. The 

 mesocarp is the true edible portion of the fruit, and is con- 

 sidered by many as a great delicacy because of its pleasant 

 characteristic flavor, slightly resembling that of the pine-ap- 

 ple. But the outer part of the fruit, the exocarp, is always 

 judiciously discarded, on account of the sharp, stinging sen- 

 sation produced upon the tongue and palate when it is taken 

 into the mouth, an effect similar to that caused by weak 

 acids. 



By placing a minute part of this exocarp under the micro- 

 scope, the cause of this peculiar action is at once shown. Groups 

 of slender, sharp-pointed, needle-like cells or fibres appear 

 half embedded in the large-celled parenchyma tissue. Care- 

 ful observation brings to view a second set of needle-shaped 

 objects, very minute, which from their regularity in shape 

 and size may at once be recognized as crystals or raphides. 



To ascertain the true nature of these raphides and fibres, 

 chemical tests were applied, as directed by Strasburger, Good- 

 ale and de Bary, with the following results: 



Acetic acid has no perceptible effect upon either form,. 



