Betrospective Criticism. 219^ 



only animal that dreams." I do not know how this position can be satis- 

 factorily maintained, involving, as it does, the necessity of proving a nega- 

 tive, and being also contrary to what we should a priori expect. The fact 

 that dogs do dream, I conclude the writer thinks sufficiently established by 

 the circumstance, so commonly to be observed, of the convulsive motion of 

 the feet, tail, and jaws, accompanied too, sometimes, with a short bark or 

 yelping, to which these animals are subject during sleep ; from which it Js 

 reasonably inferred that they are dreaming of pursuing their prey, &c. ; 

 and I feel no disposition to deny the conclusion drawn from such premises. 

 But surely the same may be predicated of cats also, who are subject, in a 

 high degree, to the very same convulsive motions during sleep, as I have 

 myself repeatedly witnessed. — W. T. Bree. Allesley Rectory , Nov. 15, 

 1828. 



Mr. Babington^s List of rare Plants in the Neighbourhood of Bath. — A cor- 

 respondent at Bath has sent you lists of what he calls the rarer plants and 

 insects found in that neighbourhood : among the plants, I was surprised to 

 find Campanula rotundifolia, Tiola tricolor, ^Solanum Dulcamara, ^lisma 

 Plantago, Epilobium hirsutum and parviflorum, Ad6xa Moschatellina, 

 Biitomus umbellatus, CXxalis Acetos^lla, iychnis dioica, iythrura Salicaria, 

 JRes^da Luteola, Spivsei'a. Ulmaria, Chelidonium raajus, iVuphar lutea, 

 Mentha hirsuta, Linaria vulgaris, ^yp^ricum perfoliatum, Tragopogon 

 prat^nsis, Eupatoriwm cannabinum ; O'rchis morio, maculata, and mascula; 

 Listera ovata, Typha, latifolia, Humulus Lupulus, T6rtula subulata and 

 muralis, ^ryum arg^nteum. All these I reckon among our more frequent 

 plants in this neighbourhood. I am aware that the local Floras vary 

 according to soil, situation, &c. ; but most of the above plants I considered 

 common in the greater part of the kingdom, which was the cause of my 

 surprise. 



Of the insects, I am not so able to speak : but Dyticus marginalis and 

 Nepa cinerea are frequently met with ; Panorpa communis in tliQ greatest 

 abundance, and iS'phinx /igiistri, Pygse^ra Buc^phala, and A'rctia caja so 

 often as not to be considered at all scarce. — Daniel Stock. Bungay, Nov. 

 17. 1828. 



Active Molecules. — M. Raspail, a French naturalist, who has taken much 

 interest in the enquiry respecting the active molecules in the grains of pollen, 

 has recently published the result of his observations. He will not admit that 

 these granules are organised bodies, he says they are minute resinous concre- 

 tions, formed in the fluid ejected from the pollen. When the drop is evapo- 

 rated they do not change their form j whereas, after evaporation, all animal- 

 cules collapse. These resinous granules were almost instantly dissolved when 

 a drop of alcohol was applied' to them. Respecting the spontaneous motion 

 supposed to be found in all inorganic substances, he says : " Ihave never 

 discovered the smallest trace of it." M. Raspail mentions some of the 

 causes of external agitation, which I enumerated in my paper on the sub-? 

 ject in your last Number ; but the most important one, the existence of 

 animalcules in river and cistern water, he has omitted. There is a species 

 of Monas, which Muller says is so small and transparent, that it is exceed- 

 ingly difficult to throw the light in such a manner as to make them per- 

 ceptible with the microscope, but at times the whole mass of water seems 

 full of them ; minute opaque particles, placed in such water, will appear to 

 be driven about by inherent spontaneous motion. 



Dr. Brewster, perhaps the most competent microscopic observer in Eu- 

 rope, has also published a paper on the subject in the Edinburgh Journal of 

 Science for April. He says, in examining the grains of pollen, " I have never 

 perceived a single motion in the least degree characteristic of animal life." 

 It would have been more satisfactory if Dr. Brewster had also stated the 

 result of his own observations. On the motions of inorganic molecules, he 

 considers the question decided by the antecedent improbability of their 



