PROGEESS OF MICKOSCOPICAX SCIENCE. 35 



synonymy is curious, and well exemplifies the difficulty cryptogamic 

 botanists find in clearly defining the limits of these lowly-organized 

 plants ; for I find that ten well-known authors describe it as a Lichen, 

 and six, equally well known, place it amongst the Fungi ; whilst it is 

 rejected by both our latest authors on these plants, Mr. Cooke, in his 

 ' Handbook on British Fungi,' 1871, merely mentioning the name of 

 DichcBna rugosa, with the remark, " I think it should be included with 

 Lichens," and the Rev. W. A. Leighton, in his ' Lichen Flora,' pub- 

 lished the same year, taking no notice of it whatever. 



Pseudo-Muscular Hypertrophy. — The ' Philadelphia Medical 

 Times ' contains a translation of an article on this subject. After 

 describing the usual symptoms and course of the disease, and the 

 microscopic appearance as being simply an atrophy of the muscular 

 fibre, accompanied by an enormous increase of the interstitial fatty 

 and connective tissue, the wi'iter passes on to the consideration of four 

 cases, which, though presenting some points of similarity, were in 

 others markedly dififerent from the ordinary coiu"se of the disease. In 

 each of these cases the disease was consequent upon an injury. The 

 fimctional derangements were not so marked as in typical cases : in 

 place of being totally lost, the power of motion was only diminished. 

 The microscope revealed, in each case, what appeared to be a true 

 hyjiertrophy of the muscular fibres, without excessive growth of the 

 interstitial connective tissue. From this it would seem that the 

 hypertrophy spreads from the muscle to the connective tissue, and 

 the hypertrophied connective tissue, pressing on the muscle, causes 

 atrophy afterwards. Schlesinger, however, rej)orts a case of a man 

 with mental disease, in whom some of the muscles were hypertrophied. 

 The microscope showed the muscular tissue much diseased, but in 

 them there was no hyjiertrophy of the muscular fibre. Whether the 

 process is a simple inflammation, or what is its nature, is not Imown. 

 — See also the ' Medical Examiner,' Chicago, May 1. 



Tlie Microscopy of Gum Production has been fully explained in a 

 paper before the French Academy by M. Prilling. The writer divides 

 the subject into three heads, as follows : — 



1. Production in vessels. — In the wood of a tree so diseased as to 

 produce gum, a large number of vessels are more or less filled with it 

 either through theii' entire length or forming a coating more or less 

 thick around them, or on one side. The most recent observers have 

 admitted that the gum results from the disorganization and transform- 

 ation of the inside of the walls of the vessels, but an attentive study 

 of the production of gum in the vessels has led me to a different con- 

 viction. The gum shows itself first in very fine droi)S, which increase 

 in size, touch each other, become confluent and form irregular masses, 

 with sinuate edges. This mode of origin of gum contained in vessels 

 appears irreconcilable with the opinion professed by German ob- 

 servers. The examination of large masses of gum taken from the 

 vessels of the apricot has led to the same conclusion. These vessels 

 are marked with areolar cavities and a spiral projection formed by a 

 thickening of the cell-walls on the interior, and the masses of gum 



