METEOROLOGY. 



469 



Rhizopoda and Infusoria, are the classes of the sub-kingdom Protozoa. Dr. 

 Grant proposed to divide Porifera into three orders, according to the material 

 of -which the skeleton is composed, whether horny, calcareous, or siliceous. 

 This division furnishes to Dr Bowerbank the orders of his class, under the 

 names of Calcarea, Silicea, and Keratosa. Calcarea is the smallest in numbers 

 as well as the lowest in position of these orders : it includes only the Sponges 

 ■which formed Fleming's genus Grantia, now divided by Bowerbank, according 

 to the structure of the skeleton, into four genera. The second order Silicea, 

 is far more extensive, and is divided according to the structure of the skeleton, 

 into seven sections or sub-orders, several of which contain numerous genera. 

 In these the skeleton is characterised as being either : 1. Spiculo radiate ; 

 2. Spiculo membranous; 3. Spiculo-reticulate ; 4 Spiculo-fibrous ; 5. Compound- 

 reticulate ; 6. Siliceo-fibrous ; or, 7. Canaliculated Siliceo-fibrous. 



T: e third order, Keratosa, consisting of Sponges with horny skeletons, is 

 likewise divided into seven sub-orders, accordingly as the skeleton is solid non- 

 spiculate kerato-fibrous ; solid semi spiculate kerato-fibrous ; solid spiculate 

 kerato-fibrous ; simple fistulo-fibrous ; compound fistulo-fibrous; regular semi- 

 areno-fibrous ; or irregular entirely areno-fibrous. 



Under these divisions, both the genera previously received and those estab- 

 lished by himself are carefully characterised by. Dr Bowerbank, in accordance 

 ■with their anatomical structure. He has added a dissertation on the discrimi- 

 nation of species, with a review of the portions of the organisation that may be 

 employed with advantage in their scientific determination, and directions for 

 the examination and preservation of specimens. 



Dr. Bowerbank's series of papers communicated to the Royal Society, sup- 

 plies a desideratum in the literature of Natural History, and his further commu- 

 nications will be awaited with much interest. W. H. 



METEOROLOGY. 



MEAN RESULTS OP METEOR iLOGICAL O'^SBRVVTIONS AT HAMILTON, C. W. 

 POlt THE YlUR 1861. 



