PROCEEDINGS OF THE SOCIETY. 303 



The thanks of the meeting were accorded to Dr. H. "Woodward for 

 the presentation of a Collection of Reprinted Papers. 



A letter was read from Miss Booth stating that Miss Sarah Monks, 

 223 15th Street, San Pedro, California, U.S.A., would like to exchange 

 Diatoms, Seaweeds, etc., with the Fellows of the Society, 



Mr. Martin Duncan read a paper " On Acari from the Lung of 

 Macacus rhesus,''^ and exhibited slides showing — 



General section of lung of Macacus rhesus showing Mites in situ. 

 Vesicle from pleura of lung of Macacus rhesus opened to show 



Mites. 

 Larva of Pneumonyssiis Griffithi from the lung of 3facacus 



rhesus. 

 Pneumonyssus Griffithi. 



The President moved a hearty vote of thanks to Mr. Martin Duncan 

 for his interesting paper, which would be published in the Journal 

 accompanied by reproductions of photomicrographs. 



The vote of thanks was carried by acclamation. 



Mr. Scourfield gave an exhibit of Marine Cladocera, and in referring 

 to the same said these forms were remarkable in that they belonged to 

 an essentially freshwater group of animals, the group in fact to which 

 such a typical pond-life organism as Daphnia also belonged. There 

 were only three marine genera of Cladocera, viz. Fenilia, Podon and 

 Evadne, each represented by a few species, but one other genus, viz. 

 Bosmina, which was otherwise entirely freshwater, was represented by 

 one species in the Baltic. Penilia belonged to the family Sididas, 

 represented in fresh water by Sida crystalUna, etc., and was peculiar in 

 possessing two lateral rostral points instead of the usual median rostrum. 

 The species of the genus were only found in tropical or sub-tropical seas. 

 Podon and Evadne belonged to the family Polyphemidge, represented in 

 fresh water by Polyyhemus and Bythotrephes. The first-named was very 

 similar to Polyphemns, but Evadne was rather peculiar and might be 

 regarded as the most characteristic marine genus of the Cladocera. 

 Both genera were probably world-wide in their distribution. The 

 species of Bosmina which occurred in the Baltic — B. maritima — was 

 very close to B. obtiisirostris Lillj., and perhaps was only to be regarded 

 as a variety of that very variable species. 



The existence of these few species of Cladocera in the sea opened up 

 the problem of why some forms could live in the sea and closely related 

 forms only in freshwater, and vice versa. This, however, was practically 



