transferred to weak alcohol, from which they are gradually 

 changed to that of 70 per cent. The forms which are contained 

 in a common gelatinous substance are fixed with chromic-acid 

 of one-half of 1 per cent and then transferred to 50 per cent 

 alcohol, where they remain permanently. 



Bryozoa 



Bryozoa are best preserved when they are treated on board 

 ship immediately after they have been caught. 



Pedicellina and Loxosoma are left for an hour in chloral 

 hydrate of 0.1 of 1 per cent and then killed with saturated sub- 

 limate, cold or hot. Wash immediately afterwards and place in 

 alcohol. Certain species of Bugula (purpurotincta, turbinata) , 

 after the animals have become well distended in a little sea 

 water, are killed quickly with hot sublimate. By pouring some 

 70 per cent alcohol slowly over the surface of the water in 

 which they are, Flustra, Cellepora, Crisia, Bugula, and Zoobot- 

 rium have been prepared in a state of complete distention. The 

 other species can be killed with the animals more or less out 

 of their cells by using a weak solution of chloral hydrate or 

 alcoholized sea water, but generally good results depend upon 

 the skill of the preparator. 



Brachiopoda 



Brachiopods are narcotized by letting them lie in alcohol- 

 ized sea water for some hours before they are put into alcohol. 

 Put a bit of cork between the valves to keep them open. Small 

 forms may be put at once into 70 per cent alcohol. 



Tunicata 



The Appendiculariae are killed by letting them rest for 

 five minutes in the chrora-osmic mixture. 



Ascidiae simplices. — To treat Clavellina and Perophora 

 so that the orifices shall remain open, first allow them to ex- 

 pand in running sea water and then immerse them in chloral hyd- 

 rate of 0.1 of 1 per cent, letting them remain from six to twelve 

 hours; then kill them with chrom-acetic No. 2 and immediately 

 afterwards transfer to chromic acid of 1 per cent, some of which 

 should be injected into the interior of each individual. After 

 a half hour transfer the animals to 35 per cent alcohol, repeat- 

 ing the injection with that fluid, and finally to alcohol of 70 

 per cent. Clavellina rissoana is usually killed in acetic acid; 

 it is not necessary to inject each individual. 



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