124 Mr John Hattray on the 



and Frullania tamarisci approximate those of Radula in size. In 

 consistence the oil hodies are semifluid, changing their form under 

 slight pressure, and resuming their original outline when the pressure 

 is removed ; when broken, round droplets of fatty oil escape. 



3. The localities where oil hodies are found in these plants are 

 various, such as in (1) foliage leaves; (2) coats of the reproductive 

 organs, i.e., of the anther idia and archegonia, as in Radida com- 

 planata, Mastigohnjum trilobatnm, &c. ; (3) stem — the oil bodies in 

 the stem cells being smaller than those in the leaf cells, and at the 

 same time larger and more numerous in the peripheric than in the 

 central stem cells, as in Trichocolea tomentella ; (4) root hairs, as in 

 Lophocolea bidentata ; (5) walls of antheridia and archegonia, as in 

 Blepharostomatrichophylla ; (6) sporogonium stalk, as in Blepharos- 

 toma trichophylla and Nardia scalaris. 



4. According to Pfefi"er, oil bodies are absent in Jungermannia 

 bicusjndata, Pellia epiphplla, Metzgeria furcata, and, according to 

 Gottsche, in Jmigermannia setacea, J. connivens, and J. divaricata. 



5. Four views have been held regarding the composition of the 

 oil bodies : — 



(1) Gottsche* believed them to be resinous or waxy, and Hof- 

 meister f also thought them resinous. 



(2) Holle X maintained that they were a mixture of oil and resin. 



(3) Schacht § said they were composed of inulin. It may here 

 be noted, that treatment with alcohol produces angular crystals 

 in the cells of Hepaticae, which dissolve on addition of water. 

 These crystals are distinct from the oil bodies. 



(4) Pfeffer regards them as chiefly composed of fatty oil, although 

 traces of wax, resin, gum or ethereal oil may be present, as well as 

 very minute quantities of water and albuminous or proteinaceous 

 substances. These results rest on the following considerations : — 



(a) Dilute alcohol, spirits of wine, benzole, turpentine, ether, and 

 carbon bisulphide cause the droplets to fuse, a fine limiting mem- 

 brane alone persisting and retaining approximately the size and form 

 of the original oil body. A second membrane may be seen in 

 Nardia scalaris, &c., after the action of absolute alcohol. 



(b) Boiling with weak potash for a quarter of an hour does not cause 

 the drops to vanish, and stronger solutions only act with difficulty. 



(c) Wax or resin is solid at the ordinary temperature, but the oil 

 bodies are semifluid, and yet traces of wax or resin may be present 

 dissolved in the fatty oil. 



{d) Ethereal oils are not present in large quantity, inasmuch as boil- 

 ing in water would remove them, and the oil bodies would change 

 • Loc. ciL, p. 289. t Pflanzenzdlen, p. 396. + Loc. ciL, p. 18. 



§ Lehrbuch der Armtomie u. Physiologic, 1856, 1 Thiel, p. 60. 



