486 



TARDIGRADA 



genus. E. arctomys, Ehrb. ; E. mutabilis, Murray ; E. islandicus, 

 Eichters ; E. gladiator, Murray ; E. ivendti, Kichters ; E. reticulatus, 

 Murray ; E. oihonnae, Kichters ; E. granulatus, Doy. ; E. spitzber- 

 gensis, Scourfield ; l E. quadrispinosiis, Kichters ; and E. muscicola, 

 Plate, are all British. More than one-half of these species are 



also Arctic, and E. arctomys is in 

 addition Antarctic. In fact, the group 

 is a very cosmopolitan one. The genus 

 is also widely distributed vertically, 

 specimens being found in cities on the 

 sea level and on mountains up to a 

 height of over 11,000 feet. 



la. Sub-genus ECHINISCOIDES 

 differs from the preceding in the num- 

 ber of the claws, the want of definition 

 in the dorsal plates, and in being marine. 

 The single species E. sigismundi, M. 

 Sch., is found amongst a^gae in the 

 North Sea (Ostend and Heligoland). 



2. Genus LTD ELLA" The long, 

 thin legs of this genus have two seg- 

 ments, and in other respects approach 

 the Arthropod limb. Marine, Plate 

 suggests the name L. dujardini for the 

 single species known. 



3. Genus MACROBIOTUS has a 

 p ia men ted epidermis, but eye-spots may 



. (From * o J J 



Plate.) ce, Brain ; k, thicken- be present or absent. The eggs are laid 

 iS mUh 6 ; rS" V o e one at a time, or many leave the body 

 phagus ; p, ? salivary glands ; at once. They are either quite free 



ph. pharynx ; sa. blood cor- . -, . , . -, rm 



puscies ; st, stomach. or enclosed in a cast-off cuticle. The 



genus is divided into many species 



and shows signs of disruption. They mostly live amongst moss ; 

 but M. macronyx, Doy., is said to live in fresh water. The 

 following species are recorded from North Britain : M. ober- 

 hauseri, Doy. ; M. Jiufelandi, Schultze ; M. zetlandicus, Murray ; 

 M. intermedius, Plate; M. angusti, Murray; M. anmdatus, Murray; 



1 P. Zool. Soc. 1897, p. 790. 



2 Hay, in P. Biol. Soc. Washington, xix., 1906, p. 46, states that the name 

 Lydella, Dujardin, is preoccupied, and suggests as a substitute 



Plate, x about 100. 



