1908.] Insect, Fungus and other Pests. 



683 



of great value at the Woburn Fruit Farm : 2 gallons paraffin, 

 i| lb. soft soap, 6 lb. caustic soda (98 per cent, pure), 28 gallons 

 water. In order to prepare this wash, the soft soap should 

 first be dissolved in 1 gallon of boiling water ; to this the 

 paraffin should at once be added (not while over the fire) and 

 the mixture churned with a syringe or force pump until a 

 cream-like emulsion results. The 6 lb. of caustic soda should 

 next be dissolved in the remaining 27 gallons of water and be 

 poured into the emulsion, the whole thoroughly incorporated 

 and the wash used at once. For small quantities for garden 

 use the proportions may be : 5 pints paraffin, \ lb. soft soap, 

 2 lb. caustic soda and 10 gallons of water. 



Teredo or " Shipworm." — From Felixstowe the Board 

 received for examination specimens of harbour piles of pitch 

 pine, which had broken off within twelve months of their first 

 being driven. The broken portions had the appearance of 

 having been eaten through and through by worms, a section 

 showing quite a honeycombed condition. The piles had not 

 been treated in any way by the use of preservatives. 



The examination of the specimens showed that the piles 

 had been attacked by Teredo, the so-called Shipworm, a 

 member of the Mollusca. The shells of this mollusc enclose 

 a small but vulnerable part of the body ; a sucker-like foot 

 can be protruded, and at the end of the shell two syphons 

 project, these being for the purpose of taking in water, which 

 carries in it oxygen for respiration and the small organisms 

 on which the Teredo chiefly feeds. 



Life History. — Eggs are produced in immense numbers and 

 remain attached to the Teredo gills. Later, after the hatching 

 of the eggs, a fry or free-swimming young stage is found. 

 These young forms, which are extremely minute, move about 

 amongst the, wood piles and later settle down on them to enter 

 between the wood fibres. The Teredo increases in size, and 

 as it grows the burrow in the wood is made larger and is lined 

 by a shell-like sheath. Into this sheath the syphons can be 

 retracted for protection and the end closed by means of two 

 calcareous pallets which are found near the point where the 

 two syphons (united for a great part of their length) diverge. 

 Several points in the life history of the pest are still obscure. 



Treatment. — Once the pest has got into the wood remedial 



