22 BURMA, ITS PEOPLE AXD PRODUCTIOXS. 



neglect. The liead abstracted and burned, the rest of the animal may be eaten with 

 impunity, as the dii-c pest is confined to the cerebral region alone. 



Class NEMATELIIINTHA. 



Order KEIM.VTODA. 



"Worm-like or filiform parasites with no segments, and ueither circulatory nor 

 respiratory organs. Soxes separate. 



The common Gordius or ' thread-worm ' of stagnant water is a familiar example 

 of tliis order. So too are the AnyuiUula or vinegar and paste ' eeh,'' and the 

 formidable 'Guinea worm.' In its young state this worm resides in water, and was 

 once supposed to be able to penetrate the skin of the bather, sportsman, or water- 

 carrier by means of one of the sudorific poi-es. It is now, however, believed that 

 it enters the system in drink, and the use of filtered water is our best protection 

 against its invasion. Once however, located in the body, it developos to a length 

 varying fi'om six iuchcs to twelve feet (Tascoe), but of no greater thickness than 

 two-thirds of a line. 



Another curious ' Xematode ' is Sphanilan'a lomhi infesting the humble bee. 

 The pregnant womb of a female of this species is 28000 times larger than the 

 animal to which it belongs, and as this prodigious development has obliterated eveiy 

 original passage, parturition is only possible by the literal falling to pieces of the 

 unhappy mother. Two most fearful parasites also belong to this order. Strongylus 

 gigas, the great kidney-worm, which grows to three feet in length, and selects for its 

 abode the kidneys of dogs, wolves, and man, and the terrible Tn'cliina spiralis, 

 which resides in the muscles of its victim, 700,000 having been counted in one 

 pound of the flesh of a man ! The original source of this pest is said to be the rat, 

 but it is received into the human frame by means of pork, and unfortunately neither 

 salting nor cooking would seem to destroy the vitality of the germs. The utmost 

 care should therefore be used in the selection of pork for food, and as a precautionary 

 measure especial care should be used to prevent pigs eating rats ; indeed, the more 

 cleanly in its house the pig is kept, and the cleaner its food and water, the safer 

 will be its flesh for man's consumption. Other noteworthy JYemafodes are the common 

 Ascaris lumhricoides, the Syngamus trachealis, whose presence in the windpipe causes 

 the 'gapes' in poultry, and the Bochiiiiua duodenalis, which, according to Pascoe, infests 

 a fourth of the entire population of Egypt. As an example of the life history of a 

 Nematode, the following account may be quoted (from Van Beneden's ' Animal Para- 

 sites ') of Ascaris nigro-venosa, whose abode is alternately the limgs and the rectum of 

 a frog. This Ascaris is a true parasite, which, when it arrives at its destination (the 

 frog), where it finds lodging and food, leaves the lungs, to go and inhabit another organ. 

 Here we have decided changes of abode in the same animal ; that which shows 

 besides that it is not a simple accident, is that the animal is of a difierent sex 

 according to the apartment (lungs or rectum) which it occupies ; here it is herma- 

 phrodite, there it is male and female. In the lungs it is veiy small and viviparous, 

 and produces young ones, which become stronger than their parents. The generation 

 which live in the lungs are hermaphrodite : the others are dioecious, that is to say, 

 the males and females have hermaphrodites for their parents. "\Ye have thus a 

 mother, a simple female or hennaphrodite, very small, whicli produces not eggs, but 

 young ones fully formed, and instead of living like tlie mother, in the lungs and 

 breathing there with greater or less facility, they go and lodge in the rectum, and 

 become not like their mother, viviparous and hermaphrodite, but oviparous and of 

 separate sexes. They produce in their turn a race, which instead of following the 

 example of their father and mother, all go olf and take up their abode in the lungs 

 like their grandmother. 



Class ANNELIDA. 

 Body segmented, legs none or rudimentary. 



