Prof. G. Gulliver on the Raphides of Onagracece. 289 



sufficient for the diagnosis ; nay, that even a seed-leaf would be 

 so was proved in (Enothera and Epilobium. 



This last fact appeared so remarkable, that I have lately made 

 it the subject of experiments with other plants, when a careful 

 examination of numerous species showed that those belonging 

 to orders previously ascertained to be regularly destitute of ra- 

 phides in the adult leaves, are also equally devoid of them in the 

 seed-leaves. Then the seeds of such Onagracese as were easily 

 procurable (to wit, Circcea lutetiana, Eucharidium grandiflorum, 

 Clarkia elegans, C pulchella, and Godetia vinosd) were sown in 

 pots ; and as soon as the seed-leaves were well developed above 

 the soil, they were all examined, and found in every instance to 

 contain raphides. These could be seen both scattered in bundles 

 throughout the parenchyma, and floating freely and singly in the 

 water wherein the part had been broken by pressure and friction 

 between the glass object-plate and cover. The raphides in the 

 green cotyledons were somewhat smaller and less plentiful than 

 in the plumule and in the fully developed stem and leaves. 



The difference in question between Onagracese and their nearest 

 allies of other orders is not only very curious, but is one of those 

 numerous phenomena which remind us how little we know of 

 the recondite operations of vegetation. Take, for example, two 

 plants, as Epilobium hirsutum and Lythrum Salicaria, similar in 

 habit and growing closely together in the same soil of the river- 

 bank, and observe the signal difference of their products, — the 

 one plant, as a regular part of its healthy structure, abound- 

 ing during its whole existence in raphides; the other as regu- 

 larly destitute of them, and affording spheeraphides instead, dif- 

 fering as much in form as they probably do in chemical com- 

 position from raphides. Supposing, then, as there is some 

 reason to do, that these crystals respectively are phosphate and 

 oxalate or some other salt of lime, a leading and constant func- 

 tion of the Onagracese would be the formation of the phosphate, 

 while the Lythracese would be a laboratory of a different salt, — 

 the performance of each of these diverse opei'ations being a re- 

 gular and special design of the plant-life in such cases. 



But though we know so little of this subject that its signifi- 

 cance remains a mystery to us, we may now make good use of 

 the facts already revealed as botanical characters, provided we 

 distinguish truly, as proposed in the last Number of the 'Annals/ 

 raphides from sphseraphides, so as not to confound such different 

 things under one and the same term, — taking care also to ob- 

 serve how far the sphseraphid-tissue (of which an engraving* was 



* The outlines of the crystals are often more or less rounded or granular, 

 not so sharp and distinct as there represented. In that Number of the 

 'Annals,' p. 228, for Cucurbitacece read Dioscoreacece, 



