Grouse Disease. 



[Sess. 



The following is the list of diatoms now exhibited : — 



Aclinantlies exilis, Kiitz. 

 Asterionella formosa, Hassal. 

 Cocconeis placentiila, Ehr. 

 Cymbella cistula, Hempr. 



II cistula maculata, Kiitz. 

 Diatoma elongatuni, Ag. 



II vulgare, Bory. 

 Encyonema ventricosum, Kiitz., var. 



minuta, Vau Heurck. 

 Fragilaria rautabilis, var. elliptica, 

 Sclium. 



M virescens, Ealfs. 



Gomphoneina capitatum, Ehr. 



II dicliotomum, Kiitz. 



II olivacenm, Ehr. 



Gomphonema olivaceum, var. vul- 

 garis, Grun. 

 11 olivaceum, var. sub- 



ramosum, Kiitz. 

 Melosira, sp. 



Navicula gracilis, Ehr., var. 

 Ti major, Kiitz. 

 n pelliculosa, Hilse. 

 11 sp. (apparently similar to 

 the unnamed form figured by 

 Schmidt (pi. 47, fig. 22) from near 

 York). 

 Synedra ulna, var. danica, Kiitz. 

 „ ulna, var. vitrea, Kiitz. 

 Tabellaria fenestrata, Kiitz. 



At this meeting Mr Hugh Eraser made some remarks on 

 the subject of " Fasciation," as found more particularly in 

 the Ash, exhibiting at the same time several interesting 

 examples of this curious abnormal growth. Mr A. Frazer 

 also exhibited and described certain objectives constructed by 

 Mr Edward Swift of London. The lenses were submitted to 

 the Society on the ground that they combined higli quality 

 with moderation in price. The objectives submitted were of 

 ^-inch and ^-inch focus, and an immersion (water) objective of 

 3^-inch focus. The last mentioned lens cost but £3, 15s., and 

 the others were equally moderate in price. At the close of the 

 meeting an opportunity was given of examining the lenses. . 



XVIIL— GROUSE DISEASE. 



By Mb TOM SPEEDY. 



{Read June 22, 1887.) 



Feom the interest taken in grouse disease by all sportsmen 

 and naturalists, it has occurred to me that a paper on this 

 subject might not be unacceptable to the members of this 

 Society. I confess to be one of those who regard these period- 



