142 SECRETORF RESERVOIRS. 



vestigated, ha\c them in abundance. According to Gulliver, cry al-containing sacs 

 are wanting in Tulipa silvestris, Fritillaria Meleagris, Lilium Martagon, candidum, 

 aurantium. whilst most other Liliacete have them in plenty : Sparganium has many 

 Raphides, the species of Typha have no crystals. Among the Lemnacese^, no 

 Wolffia has crystals ; the Lemnae and Spirodelae have numerous raphide-bearing sacs, 

 the latter having also many clusters of crystals. 



The form of the crystal-bearing sacs, and of the crystals within them, is cha- 

 racteristic for many divisions, families, and species ^ ; still general and absolute rules 

 cannot be laid down. In most families of INIonocotyledons Raphides occur exclu- 

 si\ely, or they preponderate largely, and often occur in vast quantity, e. g. Liliaccte, 

 Orchidaceaj, Bromeliacea), &c. But in species of Allium there are no Raphides, and, 

 as far as is known, crystal-containing sacs are entirely absent. Instead of these there 

 lies in the middle of each cell of the subepidermal parenchyma, on the outer side of 

 the young scales of the bulb, one prismatic crystal, or several grown together^ (this 

 is specially well seen in A. sativum). In others, e. g. the Aracese, sacs containing 

 Raphides and clustered crystals occur side by side, often in the same section. In the 

 Iridaceae only large columnar solitary crystals are to be found. While the Musacese 

 have only sacs containing Raphides, there occur in the Marantacea^ and Zingiberaceae 

 only other forms of crystals. In the Dicotyledons there are most frequently found 

 clustered crystals, or klinorhombic solitary crystals, or both forms together, often 

 also with granular crystals, while Raphides are entirely absent. In certain cases, 

 however, in these plants also the latter occur exclusively or in preponderating quantity. 

 Finally, a few further examples may be added to the above. For further details the 

 reader must be referred to the authors cited, and for the phenomena in the bast of 

 Dicotyledons to Chap. XIV, 



Clustered Crystals occur exclusively or greatly preponderate in the foliage of Cheno- 

 podiaceae, Caryophyllaces, Cactaceae, Lythraceae (Gulliver), and very many other families : 

 and, according to Sanio'', in the bast of Juglans regia, Rhus typhinuni. Viburnum Oxy- 

 coccos, V. Lantana, Prunus Padus, Punica granatum, Ptelea trifoliata, Ribes nigrum, 

 Lonicera tatarica. 



Soliiaij klinorhombic crystals in the foliage of Citrus : in the bast of species of Acer, Poma- 

 ceae, of Quiliaja Saponaria, Robinia pseudacacia, Virgilia lutea, Melaleuca styphelioides, 

 Ulmus campestris, Guajacum, Berberis vulgaris^, &c. Also in Abies pectinata. 



Sanio found solitary klinorhombic crystals and clustered crystals together in the bast of 

 Qi.iercus pedunculata, Celtis australis, tEscuIus Hippocastanuni, Hamamelis virginiana, 

 Morus alba, Salix cinerea, P'agus sylvatica, in species of Populus, Gleditschia triacanthos, 

 Carpinus Betulus, Ostrya virginica, Corylus Avellana, Tilia parvifolia. Spiraea opulifolia. 



Solitary klinorhombic crystals together ivith clustered crystals, and sacs containing granules, 

 are found in the bast of Betula verrucosa, and Alnus glutinosa (Sanio). 



Sacs containing gramdes alone, in Sambucus nigra. 



Raphides are absent in the examples of Dicotyledons hitherto enumerated. They are 

 numerous and preponderate in the leaves of species of Galium and allied genera, in the 



* Hegelmaier, Lemnaceae, p. 33. 



* P'or details of the cortex of woody dicotyledons cf. Sanio, /. c. ; there are very numerous details 

 respecting the leaves in Gulliver, Annals and Magazine of Natural History, vol. XI, XII, XIII, XIV, 

 XV, XVI. 



^ Ilanstein, Milchsaftgefasse, p. 36. 



* Monatsber. d. Berliner Academic, April, 1857. •'■ Compare Sanio, /. c. 



