Mr. Hassall on the Structure of the Pollen Granule. 551 



Molluccella lsevis. Stachys coccinea. 



Marrubium vulgare. Galeobdolon luteum. 



Ballota nigra. Physostegia virginica. 



Sideritis foetida. Dracocephalum speciosum. 



S. taurica. Westringia ermicola. 



Stachys iberica. Scutellaria galericulata. 



S. setifera. S. lupulina. 



Many of the granules of Sideritis scordioides are four-lobed. 

 Pollen grain oval, six-lobed, resembling a melon, changing its 

 form in water and emitting six pollen tubes. See fig. 51, 52. 



Gardoquia multiflora. Salvia splendens. 



Origanum heracleoticum. S. Sclarea. 



Glechoma hederacea. Ocimum basilicum. 



Monarda didyma. 

 Cylindrical, three-lobed. 



Lycopus europseus. 



Boraginace^e. 



Pollen granule of an elongated form with either rounded or trun- 

 cated extremities, centre constricted in its dry state. See PI. XIV. 

 fig. 53, 54, and PI. XV. fig. 55, 56, 57, 58. 



Pollen tubes two, opposite each other, issuing from longitudinal 

 fissures placed near the centre of the figure. See fig. 53, 54. 

 Symphytum officinale. Cerinthe aspera. C. major. 

 Pollen tubes ten ; pollen granule before the emission of the tubes 

 becoming circular. PI. XV. fig. 55, 56, 57, 58. 



Borago officinalis. 

 Number of pollen tubes not known. 



Myosotis palustris. 



Pollen tubes four. 



Anchusa semperflorens. Cynoglossum pictum? 



Pollen granule three-lobed, pyramidal. 



Onosma echioides. Echium fruticosum, 



Hydrophyllace^e. 

 Cylindrical, three-lobed. See fig. 59. 



Phacelia bipinnatifida. Eutoca multiflora. 



Eutoca viscosa. E. Wrangelana. 



Pollen granule small, triangular, sides of triangle straight ; pollen 

 tubes three. See fig. 60. 



Nemophila phacelioides. N. atomaria. N. insignis. 



Aggregos^s. 

 Plumbaginace^e. 

 Pollen granule reticulated, in its dry state cylindrical, when moist 

 somewhat triangular, with the sides of the triangle curved outwards 

 to some extent ; pollen tubes three, issuing from the angles of the 

 grain. See fig. 61. 



Armeria vulgaris. Statice latifolia. S. tartarica. 

 Statice sinuata. S. speciosa. 



Pollen granule of large size, not reticulated, cylindrical, three- 

 lobed in its dry state, when moist nearly circular ; between each lobe 



