NOTES AND MEMORANDA. 159 



When under the compressorium its horns hold it in place so that it 

 may be studied while alive with high powers. 



Trichinae. — At a soiree given at Chicago to the State Micro- 

 scopical Society of Illinois, Dr. W. T. Belfield and Mr. H. F. Atwood 

 showed some pieces of muscle from rats fed with Tricliince, on a warm 

 stage, with the worms in a living condition moving about. " It is 

 " claimed," says the ' American Quarterly Microscopical Journal,' 

 " that this is the first time that living Trichinfe have been shown in 

 " public. The value of such exhibitions in arousing a public interest 

 " in scientific studies must be very great, and we trust they will become 

 " more frequent." * 



Trichina-phobia at Berlin. — For some time past the well-founded 

 fear of trichina has led to a microscopic examination of much of the 

 meat, especially pork, sold in Berlin. Eecently the occurrence of this 

 pest there has been more frequent, and Dr. Luetdge, the Director 

 of the Microscopic Aquarium, has consented to give a course of 

 instruction in this branch of microscopy, which began on February 17. 

 The course, with practical exercises, occupies five hours, and is open 

 to ladies and gentlemen at the fee of 5s. f The catalogues of opticians 

 at Berlin have long contained as a speciality, " Achromatic Micro- 

 scopes specially constructed for Trichinae researches," and accompanied 

 by "an illustrated description of Trichina spiralis and its development." 



Organogenic Researches on the Capsule of Mosses and on the 

 Embryo of some Polypodiaceae.— M. Kienitz-Gerloff | has examined 

 Phascum cuspidatum, Ceratodon purpureus, Fumaria hygrometrica, Bar- 

 hula muralis, Atricum undulatum, &c. His results are as follows : — 



1st. The development of the sporogonium of all the Bryacefe, and 

 even of Andrcea, begins, after the preliminary transversal partition 

 of the oogonium, by the formation of an apical cell ; the latter origi- 

 nates from the segmentation produced by two septa oblique in 

 opposite directions. 



2nd. The growth of the summit of the organ ceases rather early, 

 as soon as the apical cell is divided by periclinic § or longitudinal septa. 



3rd. Each segment is divided by a radial septum into two 

 quadrants, inside which the first longitudinal partitions form an 

 endothecium which is separated from the surrounding tissue or amphi- 

 thecium; the endothecium furnishes the columella and the mother-cells 

 of the spores ; the perithecium furnishes the wall of the sporangium. 



4th. The layer of mother-cells originates on the interior of the 

 endothecium by either primary or secondary partitions ; in the former 

 case the internal sporiferous sac is formed after the layer of mother- 

 cells ; in the latter, at the same time. The cells of the columella 

 may be transformed into a fertile tissue producing spores. 



5th and 6th. The first longitudinal partition which takes place in 

 the amphithecium separates from it the external sporiferous sac, whose 



* ' Amer. Quart. Mic. Journ.,' vol. i. (1879) p. 167. 



t ' Nature,' vol. xix. (1879). 



X ' Botanische Zeitung,' 1878, Nos. 3 and 4. 



§ That is, convex in the same direction as the jieriphery. 



