1897] MICROSCOPICAL JOURNAL. 267 



cover were 1.5 per cent., 1.4 per cent., and 1.3 per cent., 

 and these were present only at the heig^ht of the illness, 

 sinking- back very shortly to 0.7 percent., 0.1 per cent., 

 and per cent, respectively. 



The maximum of myelocytes found in the blood of those 

 who died of diphtheria was 16.4 per cent. On the other 

 hand, eig-ht cases died without any noticeable increase in 

 the quantity of myelocytes. The author cannot yet state 

 at what day of the illness a bad prog-nosis may be made, 

 but in one case in which he was able to examine the blood 

 on the fourth day he found 12.8 per cent, myelocytes. 

 The first case died seven days later; the second, eig-hteen 

 days after. 



Interesting observations are recorded with regard to 

 the numbers of other white cells, eosinophil cells, etc; but 

 apparently no very definite conclusions can be formed 

 with regard to them. 



BIOLOGICAL NOTES. 



Chalk. — A sheet of chalk more than 1,000 feet in thick- 

 ness underlies all that portion of England which is situated 

 to the southeast of a line crossing the island diagonally 

 from the North Sea at Flamborough Head to the coast of 

 the English Channel in Dorset. This massive sheet of 

 chalk appears again in France and as far east as the Crimea 

 and even in Central Asia beyond the sea of Aral. There 

 can be little question that all these now isolated patches 

 were once connected in a continuous sheet, which must, 

 therefore, have occupied a superficial area about 3,000 

 miles long, by nearly 1,000 broad. These enormous 

 deposits are made up of the microscopic remains of min- 

 ute sea animals. 



Hair on the Pulvill lof Flies. — With regard to the diffi- 

 culty respecting the hairs on the pulvilli of flies, is it to be 

 expected that the hairs should be hollow, and in the nat- 

 ure of ducts for the viscid fluid secreted b,y the glands ? 

 Do they — the hairs — not act rattier as a simple mecnhaical 



