50 ORDERS. 



Examples. Tipula, (crane-fly) culex, (gnat) 

 asilus, (hornet-fly) empis, bombilius, musea, 

 (house-fly) tabanus, (great horse-fly) conops, oes- 

 trus, (gad-fly) hippobosca, (common horse-fly.) 



IX. CLASS MOLLUSCA 



IS DIVIDED INTO FOUR ORDERS. 



1 . NUDATA, destitute of a shell. 

 Examples. Slug or naked snail, cuttle-fish. 



2. MULTIVALVA, having shells with more than 

 two valves-. 



Examples. Barnacles, acorn- shells. 



3. BIVALVA, having shells with two valves. 

 Examples. Clams, oysters, scollops. 



4. UNIVALVA, having shells with single valves* 

 Examples. Snails, conk-shells. 



X. CLASS ECHINODERMA 



IS DIVIDED INTO TWO ORDERS. 



1. PEDICELLA, having stem-like organs, which 

 are applied by the animals for the purpose of loco- 

 motion. 



Examples. Asterias, (star-fish) echinus, (sea* 

 hedgehog) holothuria. 



2. APODA, having no organs for locomotion. 

 Examples. Siponculus, molpadia, minyas, 



XL CLASS INTESTINA 



IS DIVIDED INTO TWO ORDERS. 



1. CAVITORIA, having internal cavities and a 

 mouth* 



