enough to keep the colony in proper position within it. It should 

 be plugged with cotton and placed within a larger tube filled with 

 70 per cent alcohol and closed with a cork. This double-tube 

 system prevents movement of the liquid about the colony itself, 

 even when the outer tube is not entirely filled with alcohol. It 

 is likewise very useful for shipment of specimens, and especially 

 so for purposes of demonstrations. It is recommended for all 

 very delicate animals and those with appendages which can be in- 

 jured easily. 



Apolemia uvaria is killed as are the preceding species 

 and hardened with 1 per cent chromic acid, which is substituted 

 (in the same dish) for the sulphate of copper arid sublimate mix- 

 ture which has been drawn off through a siphon. After twenty 

 minutes in the acid, wash in fresh water and transfer to alcohol, 

 the change of fluids being effected by means of siphons. 



Rhizophysa should be allowed to expand in a beaker with 

 the least practicable amount of water and should then be killed 

 with hot saturated sublimate. Wash at once and put into weak 

 alcohol, rearranging as far as possible the nettle-filaments and 

 tentacles which have become tangled during the handling. 



Physalia caravella should be permitted to expand its append- 

 ages and polyps in a tall cylinder filled with clear sea water, 

 taking care not to touch the pneumatophores on account of their 

 severe stinging action. The preparation succeeds much better in 

 a very high cylinder, on account of the great extensibility of the 

 nettle-filaments. When the colony is well distended pour over it 

 a volume of the sublimate and acetic acid mixture equal to one- 

 fourth that of the sea water containing it. As soon as dead, the 

 colony should be transferred in the same manner as at first, to a 

 similar cylinder containing chromic acid of one-half of 1 per cent 

 and after twenty minutes to 50 per cent alcohol, and finally to 

 that of 70 per cent. 



Hippopodius, Caleolaria, and Abyla. — Kill with the mixture 

 of sulphate of copper and sublimate and put directly into weak 

 alcohol. The bell of Abyla is also well prepared with the chrom- 

 osmic liquid. 



Praya is fixed like Hippopodius, but is hardened in the 

 mixture of potassium bichromate and osmic acid, where it may re- 

 main one or two days. 



Diphyes.-Use hot sublimate for killing, with the chain 

 of the individuals distended. 



Velella is killed with the chrom-picric mixture, or with 

 that of sublimate and chromic acid, and after a few minutes is 

 removed to weak alcohol. 



Porpita is slowly killed by dropping with a pipette a few 

 drops of Kleinenberg ' s solution into the beaker where it has be- 

 come distended. When the beautiful blue color of the colony has 



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