ENTOMOLOGIST AND BOTANIST. 



255 



the several treatments required for each species. 

 Premature planting of the definite class, or the 

 neglect of suitable conditions, or of proper early 

 cultivation, or any treatment that gives them 

 age without corresponding growth, invai-iably 

 diminishes the product. The definite class of 

 tropical species requiring a high temperature 

 for their development soon acquire the habit of 

 suiting them? elves to their new conditions, and 

 complete their vegetative processes throughout 

 in a much shorter time than when in their na- 

 tural habitats, as if not to be defeated, by those 

 unfavorable conditions, of the object of their 

 existence, viz., the produ<-tion of seed— the 

 functions of growth are suspended in dne time 

 to allow for this to be accomplished, while the 

 indefinite class go through the whole season 

 maturing and producing vegetable growth as 

 well as seed, and as the best results with this 

 class are obtained by the longest time, the earli- 

 est planting is most successful — age with this 

 class is in nowise detrimental, rather profitable. 

 The Squash family {Cucurbitaceoi) , Potato fam- 

 ily (Solanacew) , Mallow family (Jfalvacece) , 

 the Pea family, in part, and many other orders 

 to some extent belong to this indefinite class. 

 All the cereals, the Compositce, and also the 

 great majority of other orders belong to the 

 definite class. E. Hall. 



VEGETABLE CELLS. 



EY DR. FELIX SCUAAN, CHICAGO. 

 TAUT II. 



The second part of the vegetable cell is the 

 nitrogenous or primitive utricle (utricidus jiri- 

 mordialis). It is a half solid delicate membrane 

 of nitrogenous matter lining closely the interior 

 of the cellulose membrane. 



[Vis- llil-l 



In all cells mentioned above I was unable to 

 discover the existence of this membrane, and 



some days ago I wrote a note tending to de- 

 monstrate that this membrane does not exist in 

 fact. But being careful I discovered it in the 

 hair which grows on the stem of Geranium. 

 This hair has the shape of a pharos or light- 

 house. It is composed of four cells, the infe- 

 rior in connection with the epithilial cells is 

 conical, having a large base, and diminishing 

 until the half of the length of the hair where it 

 is attached to the two other quadratic cells, also 

 both conical in shape. On the top ot the third 

 we find a larger spherical body which presents 

 also the side wall of the cellulose membrane 

 (Fig. 161, «') and \&y shrunken on one side. 

 During this time the cytoblasf was distinctly to 

 be seen. 



I was not satisfied with that result because I 

 could not distinguish the membrane isolated, 

 and the retiring of the contents could be ex- 

 plained as a folding of any nitrogenous sub- 

 stance without any genuine coat. That doubt 

 left me considering the following experiment 

 with the spherical head-cell of the hair. 



The successive action of the sulphuric ether 

 upon it gave place to a hole in the cellulose 

 membrane, which here also grew successively 

 larger by the retiring of the contents. (Fig. 

 161, V' b"). I remarked in this case also the 

 cytoblast more distinctly. I also observed a 

 double contour on the retiring membrane, but 

 the conviction that it was really a membrane 

 was enforced by the partial isolation of the 

 iitriculus primordialis, which I performed by a 

 rubbing pressure of the covering-glass. The 

 design presented itself as a leak or crevice (Fig. 

 161, rj) in the cellular membrane, permitting the 

 primitive utricle to escape in part, prolapse-like, 

 showing its cytoblast clearly. Was that a mem- 

 brane V 



The ether evaporated raiiidly aiul formed a 

 concave meniscus between the two glass-plates, 

 like every fluid wetting the glass. The power 

 of this retiring meniscus can be calculated by 

 stated physical laws, into which I will not here 

 enter. I will only state that this power of the 

 retiring concave meniscus of the evaporating 

 ether was strong enough to bend the prolapsed 

 primitive utricle over the inferior edge of the 

 leak in the cellular membrane. (Fig. 161, /;). 

 By adding a drop of ether, the elasticity of the 

 membrane equalized the bending again, and the 

 prolapse took its prior shape. Was it a mem- 

 brane? 



Acetic acid reabsorbed most of the contents. 

 (Fig. 161, *'). This part of my study was troub- 

 led by losing the object out of sight a moment, 

 and when I found it again, the primitive utricle 



