388 University of California Publications in Zoology [Vol.22 



(series 1, sample 2) "were allowed to remain on the bottom of the 

 aquarium for about six months before being pipetted off. 



The borings as collected were dried overnight at 100° C. in an 

 electric oven, and crushed to pass a wire sieve having 50 meshes to 

 the linear inch. Samples of the original wood were reduced to saw- 

 dust, then ground to pass through the 50-mesh sieve. To avoid 

 changes in moisture content, all samples were preserved for analysis 

 in tightly fitting glass stoppered bottles. 



• Methods of Analysis 



Analyses were made for moisture, ash, calcium, nitrogen, benzene 

 extract, alcohol extract, reducing sugars in alcohol extract, hemi- 

 eelluloses, cellulose, lignin, and furfural yield on distillation with 

 hydrochloric acid. All these determinations were made on one sample 

 of wood and the corresponding sample of ejected borings. On subse- 

 quent samples some of the determinations were omitted. "Whenever 

 possible determinations were made in duplicate, but in some instances 

 the limited amount of available material made it necessary to depend 

 upon single determinations. 



1. Moisture. — One gram was dried for seventeen hours at 100° C. 

 in a constant temperature electric oven. 



2. Ash. — The dried material from the moisture determination was 

 transferred to a platinum dish and incinerated over a wire gauze at 

 a temperature below redness. 



3. Calcium. — The ash was digested in dilute hydrochloric acid and 

 the dissolved calcium estimated by precipitation as oxalate in slightly 

 acid solution, and titration of the precipitate with permanganate. The 

 conditions of precipitation were essentially those of McCrudden 

 (1909). 



-1. Nitrogen. — Seven-tenths gram of material was treated by 

 Gunning's modification of the Kjeldahl method. The results were 

 calculated as protein by multiplying the nitrogen value by the factor 

 C.25. 



5. Benzene extract. — One gram of the material was weighed out 

 into an alundum extraction thimble and dried at 100° C. for several 

 hours, then extracted for six hours in a Soxhlet apparatus. The 

 benzene was evaporated off and the residue dried at 100° C. and 

 weighed. 



6. Alcohol extract. — The residue remaining in the thimble after 

 the benzene extraction was extracted with 95 per cent alcohol for six 



