774 SUMMARY OF CURRENT RESEARCHES RELATING TO 



ground. The surfaces on which the vessels stood were either slate or 

 dull white brick, but there was always a layer of the fluid some 2 cm. 

 thick between the bottoms as well as between the sides of the two 

 vessels. The coloured solutions employed consisted of the following : 

 for red, a strong solution of erythrosin in distilled water, the strength 

 being increased until a 2 cm. layer cuts out all the orange. Weak 

 lithium carmine solution in a 2 mm. layer was also used. For green, a 

 60 p.c. solution of copper chloride with a trace (^V vol. used) of 6 p.c. 

 potassium chromate gave a good result in 1*5 and 2 cm. thickness. 

 For blue, ammoniacal solution of copper sulphate was used, a strong 

 ammonia being added to a concentrated solution until the precipitate 

 thrown down could be filtered off ; this screen, owing to the ammonia 

 fumes, is very toxic. The light employed was direct, or direct and dif- 

 fuse, daylight. In the former case the vessels stood for more than half 

 their depth in a tank placed on the south side of Plymouth laboratory. 



Studying the Development of Aplysia punctata.* — A. M. C. Saun- 

 ders and Margaret Poole obtained Aplysia punctata in large numbers 

 until the middle of June. There was no difficulty in keeping them in the 

 aquarium, and they laid eggs in great quantities. Early in the summer 

 the eggs were attacked at times by bacteria, and later in the year by 

 algge. The rate of development was found to vary with the temperature 

 of the water. In April, about fifteen days elapsed between the deposition 

 of the eggs and the emergence of the free-swimming larvae. The 

 authors failed to rear the larvae beyond the free-swimming stage. 



Cultivation of Meningococci. t — The examination of fluid from a 

 lumbar puncture for meningococci is a simple process when the organisms 

 are numerous, but in many cases, when they are scarce, the ordinary 

 methods of cultivation upon ascitic or hydrocele agar give negative 

 results. Ft. Bruynoghe recommends instead the use of the spinal fluid 

 itself. This is added in definite quantities to broth-tubes, and after a 

 few hours incubation a definite pellicle makes its appearance, consisting 

 of meningococci in pure culture. In cases of mixed infection or con- 

 tamination this method will not be successful. If the fluid be very 

 purulent the fluid is allowed to settle, and the upper clearer fluid is 

 inoculated as above into broth-tubes. Comparative investigations show 

 that this method gives much better results than that which involves the 

 use of ascitic agar. 



(2) Preparing- Objects. 



Automatic Fixing and Imbedding Apparatus.} ■ — Gr- Arndt de- 

 scribes a machine (figs. 112-114), the use of which would save a consider- 

 able amount of tiresome manipulation in pathological laboratories. It 

 receives portions of fresh tissue, and after due time returns them 

 imbedded in paraffin, ready for cutting. The apparatus consists of three 

 principal parts, a thermostat, a cover e carrying a metal cage fcoanda 

 clock, which controls the automatic mechanism by means of electrical 

 contacts. The inner casing of the thermostat carries a circular series of 



* Quart. Joum. Micr. Sci., lv. (1910) pp. 498-9. 



t Centralbl. Bakt., l'e Abt. Orig., lvi. (1910) pp. 92-4. 



X Muencb. Med. Wockenschr., lvi. (1909) pp. 2226-7. 



