128 MR. HENFREY ON THE DEVELOPMENT 



of the important investigations of Count Suminski, which were first made known in 

 the 'Bulletin' of the Berlin Academy, and hy a note from Dr. J. Munter in the 'Bota- 

 nische Zeitung,' but were given in a complete form in a separate treatise by the author 

 in 1848*. 



These investigations, which form the basis of the subject before us, from the capital fact 

 of the discovery of the archegonia and of the development of the embryo from one of these, 

 present a curious mixture of industrious observation and preconceived theories. It is an 

 invidious task to criticise an essay which has so greatly advanced our knowledge of the 

 subject, but it is an unavoidable one. The great fault of the essay is the free exercise of 

 the imagination in cases where the delicacy of the structures renders the objects exceed- 

 ingly difficult to make out clearly. I feel warranted in making this assertion by the fact 

 that my own microscope must be equal if not superior to that used by Count Suminski, 

 since I have seen, with the greatest clearness, points which he missed, where good defi- 

 nition of the microscope was all that was requisite, and on the other hand, I can trace 

 actual invention in cases where bad definition of the object would leave points obscure 

 which I saw distinctly. Moreover, his figures display appearances which I neither saw 

 nor can conceive the possibility of seeing with the distinctness represented in his drawings, 

 while some of these bear patent evidence of a faulty interpretation of tolerably clear con- 

 ditions. 



Such assertions of course require evidence, and it is desirable that this should not rest 

 upon counter-statements alone, but should furnish some explanation of the probable causes 

 of the errors stated to exist. 



In the first place, then, Suminski describes the growth of the cells of the prothallium 

 to take place by the formation of two or more free cells within a parent-cell, expanding till 

 they come in contact, and meanwhile displacing the chlorophyll and other contents of the 

 parent-cell, which become absorbed and are reproduced in the new cells. This statement 

 is opposed to all my experience of vegetative growth, not only in these prothallia, but in 

 all other plants ; and is evidently a hasty conclusion, arising out of a preconceived notion, 

 — that notion of cell-formation formerly asserted by Schleiden to be universal, but now 

 acknowledged by him to be subject to exception : for I can affirm that the growth of the 

 prothallium occurs by the expansion and subdivision by septa of the cells, without im- 

 portant disturbance of the contents, and this process is in all probability effected through 

 the agency of the primordial utricle, or layer of dense protoplasm which invariably lines 

 the walls of the growing cells. 



"With regard to the antheridia, Suminski observed them very superficially ; he describes 

 the compound cellular body borne upon a peduncular cell, as a simple cell, discharging 

 the sperm-cells by bursting. He overlooked therefore all the stages of development, fror 

 the very earliest up to the time just preceding the dehiscence, and can scarcely have paic 

 any attention to the appearances of the effete antheridia. I need only refer to the obser- 

 vations of Thuret, Schacht and Hofmeister to prove how imperfect his account of the 

 antheridia is. The spermatozoids inside the antheridia, again, and those in the fre 



* Zur Entwickelungsgeschichte der Farrenkriiuter, von J. Grafen Leszczyc-Suminski. 4to, Berlin, 1848. 



