for the Min-oscope. 105 



846. LITTLE VAULTER (Canthocamptus minutus). 

 Smaller than Cyclops, with shorter antennas, and but one 

 ovary. Ponds and ditches. 



847. The DIAPTOMUS (Diaptomus castor}. Antennae 

 large and strong, with twenty-six articulations. Ovary 

 single. In ponds. 



848. RIBBED WATER-FLEA (Camptocercus macrouru ,. 

 Ovoid; pellucid; finely ribbed longitudinally. Beak 

 rounded and blunt. Eye small. Ponds and ditches. 

 (PI. XI., fig. 1 6.) 



849. FISH LOUSE (Argitlus foliaceus). This curious 

 parasite may often be found crawling slowly over the body 

 of the pike and other fish. It has some resemblance in 

 form and size to the bed-bug. 



PARASITES. Animals of all kinds are more or less 

 subject to parasites, quadrupeds and birds especially, 

 several kinds being sometimes found on the same host. 

 These parasites may be fleas, lice, mites, or ticks; and 

 under these four heads the majority may be classed. The 

 following are common examples of each group : 



850. CAT FLEA (Pulex fells). This flea is of a pale 

 pitchy-brown colour; the head is naked and shining, with 

 scattered dots. Common on the domestic cat. 



85 1. DOG FLEA (Pulex cauls}. Similar in colour to the 

 last, with the head punctate behind, the lower part of the 

 head and the protothorax with a comb-like fringe. This, 

 as well as another species, is not uncommon on the dog. 



852. MOLE FLEA (Pulex talpa:}. This species has a 

 long and slender body, and is found in company with a 

 tick and two species of mites, as a parasite on the mole. 



853. MOUSE FLEA (Pulex musculi). This little flea 

 is occasionally found on the mouse ; but it often happens 

 that a number of mice will be examined without meeting 

 with a single specimen. 



854. FOWL'S FLEA (Pulex galling) has an elongated 

 head, and a comb-like fringe to the protothorax. Not 

 uncommon on the barn-door fowl 



