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FIG. 52. Various types of spermatozoa. A, B. The Teleost, Leuciscus 

 (Ballowitz). C, D. The birds, Phyllopneuste and Tadorna (Ballowitz). E, F. 

 Two forms of the sperm of the snail, Paludina (von Brunn). G. The Nematode, 

 Ascaris (Van Beneden). H. The Annulate, Myzostoma (Wheeler). I. The 

 bat, Vesperugo (Ballowitz). J. The opossum, Didelphys (Wilson). K. The 

 rat (Wilson). L. The Urodele, Amphiuma (McGregor). M. The Crustacean, 



