[21] THE PRESERVATION OF MARINE. ANIMALS HOVEY. 



proceed with their preparation as soon as possible after they have been 

 taken from the sea. Certain Oampanularidse in particular, such as 

 Aglaophenia, Plumularia, Sertularia, and the like, which live iu deep 

 water, almost always arrive at the laboratory in a damaged condition 

 or dead. They are more easily injured than other forms by the dredge, 

 the bottom net, or other fishing apparatus. The best plan to follow 

 with such specimens is to pat them directly into alcohol, to preserve 

 the perisarc at least. To treat the animals perfectly, they must be 

 attended to on shipboard as soon as caught. 



Other forms which live at less depth, and which can be fished by 

 using every precaution against injuring them, must be handled with 

 great rapidity, otlierwise, after a short time, the polyps become 

 retracted, and it is very difficult to kill them in an expanded state. 

 In general, these forms are more contractile than the Tubularidse. 



All the Hydroidea — that is to say, the permanently polypoid forms, 

 with very rare exceptions — are killed with hot saturated sublimate. If 

 the polyps are not in complete expansion when received, the colonies 

 should be allowed to expand in beakers of fresh sea water. As soon as 

 the fixing fluid has been poured over the animals the whole should be 

 turned into a crystallizing dish, containing fresh water, to cool ; then the 

 animals should be removed to another dish of fresh water for washing, 

 and after five minutes to weak alcohol (50 per cent). If it is desired 

 to avoid the heating of the liquid, cold sublimate can be used, but only 

 for the Tubularidse. 



Large colonies of Tubularia and Pennaria are killed with the mixture 

 of sublimate and chromic acid in volume equal to that of the water in 

 which they are, and after a few minutes they are washed and removed 

 to alcohol. Antennularia may be killed in cold sublimate, washed in 

 fresh water, and placed in 50 per cent alcohol, and so on. 



MEDUSA FORMS OF THE TUBULARID^. 



The small forms, Eleutlieria {Glavatella), Gladonema, Podocoryne, and 

 the like, are killed with the mixture of sublimate and acetic acid, used 

 in large proportion. Eleutheria may be killed with Kleinenberg's 

 solution. 



Lizzia TioelUlceri and Oceania pileata, as soon as the tentacles have 

 become well distended, are killed with concentrated acetic acid and 

 immediately poured into a tube containing the mixture of alcohol and 

 chromic acid. By gently agitating the tube the animal regains its 

 normal form. After remaining in the mixture about fifteen minutes it 

 is placed in 35 per cent alcohol, and then gradually transferred to that 

 of 70 per cent. Another and perhaps better way of handling these 

 forms is to allow them to expand in a specimen tube less than half full 

 of water, and when they are well distended to fill the tube with acetic 

 acid. Transfer them at once by pouring into the tube containing the 

 mixture of alcohol and chromic acid. A few minutes later pour out a 

 small portion of the liquid in the tube and add chromic acid, because 



