Invertebrate Types 



1, Hydra; 2, earthworm; 3, a troehopliore larva; 4, a rotifer; 5, Ba- 

 lanoglossus; 6, Trochosphara; 7, Aiiipliioxus; 8, a tunicate; 9, Bonellia; 

 10, a fresh water annelid reproducing by fission. Fig. 3, from Korsehelt 

 and Heider after Hatsehek; 4, from K. & H. after A. Agassiz ; 6, from 

 K. & H. after .Semper; 9, from Doncaster; the others are original, 9 

 from a preparation by Powers. Fig. 1, i, intestine ; m, mouth ; t, ten- 

 tacles. Fig. 2, c, crop; ce, coelome; g, gizzard; i, intestine; m, mouth; 

 n, nerve cord; np, nephridium (kidney) ; sv, seminal vesicles; sr, seminal 

 receptacles; ph, pharynx. Figs. 3 & 4, a, anus; ev, contractile vesicle or 

 bladder; e, excretory duct; i, intestine; m, mouth; mx, niastax (grind- 

 ing pharynx) ; pr, pre-oral, and po, post-oral ciliated rings; pg, pharyn- 

 geal glands; s, stomach; o, ovary. Fig. 6, c, cloaca; e, excretory duct; 

 m, mouth; mu, muscle; pr, pre-oral, and po, post-oral ciliated rings; 

 o, ovary; pg, pharyngeal gland. 



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