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9 



PllOGKESS OF MICROSCOPICAL SCIENCE. 



Vegetable Parasites in Corals. — lu the ' Proceedings of the Eoyal 

 Society' (No. 164), in a long and valuable paper by Mr. H. N. 

 Moseley on corals found during the ' Challenger ' expedition, there 

 appears the following note on the question of parasitism : — The 

 corallum of both Millepora and Pocillopora is permeated by fine 

 ramified canals, formed by parasitic vegetable organisms of the same 

 nature as those described by Dr. Carjienter and Professor Kolliker as 

 occurring in the shells of mollusks, &c. The organisms were found 

 in abundant fructification ; they are green, but otherwise ajipear to be 

 fungi, as are the pai'asites of shells, &c. Similar parasites are to be 

 found in various coralla from widely distant parts of the world. 



Form and Size of the Batrachian Blood-corpuscles. — Professor Gul- 

 liver, F.E.S., in his recent paper before the Zoological Society makes 

 the following observations on the blood-globules of the Batrachia : — 

 On each broad surface they are generally flat or somewhat vaulted ; 

 and their outline is regularly a well-defined oval figure, mixed occa- 

 sionally with a few of a suboval or even circular shape, as indeed is 

 the case among all regularly elliptical blood-disks, though this is 

 rarer in Birds than in the lower classes and in the Camels. In 

 Batrachiaus, the short diameter of the corpuscle being taken as 1, its 

 long diameter would vary commonly between 1.*- and 12^. The thick- 

 ness of the corpuscle is about one-third of its short diameter ; and the 

 nucleus may be either subrotund, or more commonly liker in shape to 

 the envelope. The largest red blood-corjniscles of Vertebrates occur 

 in the tailed Batrachians, of which AmpMuma, a cauducibranchiate 

 species, has the largest of all, so that these are visible to the naked 

 eye, and the perennibranchiate Proteus the next in size ; and in 

 Sieholdia, which has deciduous gills, the corpuscles are larger than in 

 Siredon, which has permanent gills. In Amphiuma and Proteus the 

 corpuscles are at least thrice as large as in some Frogs and Toads — 

 an amount of difference of which there is no example either in the 

 class of Birds or Reptiles, though it is exceeded among Apyren?emata, 

 The corpuscles in the anurous Batrachians are not always bigger 

 than, and sometimes not so long as, in a few EeiDtiles and in some 

 Sharks and Pays. The size of the corpuscles in Batrachians may 

 differ in the same individual at different seasons. A few more obser- 

 vations on the corpuscles in this class are given in the ' Proceedings 

 of the Zoological Society,' February 4, 1873. 



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