40 



CLASSIFICATION OF THE ANIMAL KINGDOM. 



CLASS II.-NEMATELMIA (Round-worms). 



ORDER I. ACANTHOCEPHALA. EcliinorhynchiLs (fig. 34). 



(Pagenstecher, Echinorhynchus proteus, Zeitschr. fiir Wiss. Zool., 1863 ; 

 Lindemann, Anatomic der Acanthocephalen, Moscow, 1865 ; Von Linstow, 

 Zur Anatomie und EntwicJcelung von Echinorhynchus angustatus, Archiv 

 fiir Naturg., 1872.) 



ORDER II. GORDIACEA (Hair-worms). 



Fam. a. Sphaerulariidre. Sphcerularia. 

 Fam. b. Gordiidee. Gordius (fig. 35). 

 Fam. c. Mermitidse. Mermis. 



(Lubbock, On Sphcerularia bombi, Natural History Review, 1861 ; A. 

 Villot, Monographic des Dragoneaux (Gordiidse), Archives de Zool. Exper., 

 1874.) 



Fig. 34. Acanthocephala. A, Echinorliyn- 

 chus gigas, slightly enlarged. B, Head of the 

 same, still further enlarged. 



Fig. 35. Gordiacea. A, A small 

 individual of Gordius aquaticus, of the 

 natural size. B, Larva of Gordius sub- 

 furcatus, with its piercing proboscis 

 and two rows of hooks, enlarged. 



