504 Mr. Valentine's Supplementary Observations on 



a few minutes being allowed to intervene between each addition, the outer coat 

 only of the sporules will be ruptured and the contents will be ejected in the 

 mass, being still enveloped by the delicate internal lining membrane of the 

 sporule. Notwithstanding all the care that maybe employed, a large majority 

 of these sporules will have both their coats ruptured, and the contents will con- 

 sequently be scattered. The sporules of Jungermannia complanata and J. dila- 

 tata are much better fitted for the experiment. The sporules of the former spe- 

 cies, in their natural state, are of a rich olive-brown colour, and are completely 

 filled with minutely granular matter (Tab. XXXV. fig. 1.). On the addition 

 of a small portion of acid a few of them immediately burst and the contents 

 are scattered (Tab. XXXV. fig. 6.), but the majority acquire a border of a 

 deep-red colour, the contents appearing to be collected more towards the 

 centre of the cavity, and they become more irregular in shape, with a projec- 

 tion on one side (Tab. XXXV. fig. 2.). Upon the addition of a little more 

 acid the outer coat is slowly ruptured, and the contents are gradually squeezed 

 out, the passage appearing to be a work of great labour, giving an observer 

 the idea of parturition in animals (Tab. XXXV. fig. 3.). When the contents 

 are nearly out the action is more rapid, and they are ejected with force, the 

 sporule recoiling and contracting the fissure with a spring, unless, as is some- 

 times the case, the sporule is so much lacerated as to lose its elasticity. 

 Whilst the contents were passing out they were forcibly compressed by the 

 orifice into an oblong shape ; or, if the fissure happened to be small, they would 

 be pressed into the form of an hour-glass ; but the moment they are free they 

 resume the globular form, and appear like a spherical mass of slimy granules 

 of a faint greenish-blue colour (Tab. XXXV. fig. 5.). The fact of the granules 

 being evacuated in the mass, together with the peculiar appearances which 

 they present in the act of passing out, fully impress the observer with the belief 

 that they are held together by some power either of a gelatinous cohesion of 

 the granules amongst themselves, or by their being inclosed in a membi'anous 

 sac. This last supposition is proved to be the real fact, by allowing the spo- 

 rules to remain in the acid for twenty-four hours, when the mass of granules 

 will be found to have contracted into a smaller and apparently organized body, 

 which in some of the instances may be clearly ascertained to be surrounded 

 by a highly delicate translucent membrane in the form of a hollow sac, about 



