and Laboratory Methods. '^709 



Battery jars with gauze cover held in place by strings of adhesive plaster were 

 ordinarily used for keeping mosquitos in confinement. A small dish of water 

 containing some living grass is placed in the jar and food is supplied in the 

 form of lump sugar hung in a gauze bag at the top of the jar. In the hot moist 

 climate of Havana this was found to be preferable to banana, often recommended 

 as a food for mosquitos. Watermelon, apples or other fruits may also be used. 

 In such jars Culix has been kept alive for more than five months. c. a. k. 



Hamburger. C. Beitrage zur Kenntnis von TracheUus is one of the largest and 



Traciuiiiis ovum. Arch. f. Protistenkunde also One of the rarest of the infusoria. 



2: \-\z, Taf. i, 2, mit. 4 Textfiguren, 1004. .^ , . tt -j il • l 1 j 



■^ - t b ^/ n It was found near Heidelberg in shaded 



ponds full of fallen leaves in September-November. Leaves and pond water 

 were brought into the laboratory with a gradual transition from field to room 

 temperatures. In a few days the sides of the culture dishes were covered with a 

 heavy growth of Epistylis, among which TracheUus was soon to be found in 

 abundance feeding upon its zooids. 



Preservation of TracheUus is difificult on account of the large amount of water 

 in the animal. Sublimate, sublimate-acetic and formol all failed, but osmic 

 vapor in 1 per cent, osmic acid preserved not only the bodily form but also the 

 internal structure. To prevent blackening the osmic acid was washed out by 

 water after a few minutes. Flemming's and Hermann's fluids also gave excel- 

 lent results. Ectoplasmic structures were demonstrated in osmic material by 

 adding a few drops of 5 per cent, aqueous solution of sodium bicarbonate and 

 allowing the solution to concentrate by evaporation. When the demonstration 

 reaches the desired point the solution is replaced by dilute glycerine. The 

 clearing and embedding processes were carried on in small glass cylinders 2 x ..5 

 cm. whose lower opening was closed by fine bolting cloth. This container can 

 be readily passed through vessels of chloroform, chloroform-paraffin and melted 

 paraffin and then embedded. When the paraffin cast is cold the cylinder can 

 be cut out, the silk diaphragm removed and the paraffin cylinder pushed out 

 from the slightly warmed glass tube. This method is readily applicable to other 

 small objects. c. a. k. 



i-.T T^- AT vj J ,^ ,r 1.T , The animals were narcotized by the 



List, I. Die Mytiliden des Golres von Neapel 



und der angrenzenden Meeresabschnitte. addition of "2 per cent. COCain in sea 

 Fauna u. Flora d. Golfes v. Neap. Monogr. water, the amount being gradually 

 27: 312 pp, 17 figs. u. 22 Taf. 1902. . , ^, .1 



increased. Care must be taken, espe- 

 cially with young individuals, not to prolong the narcotization until maceration 

 begins. When the whole animal is to be fixed a piece of wood or cork is placed 

 between the valves of the shell before the fixing agent is added. If individual 

 organs only are to be fixed these are dissected out under water. If the whole, 

 or a part of the shell remains attached the fixing agent should contain some free 

 acid. For anatomical preparations"*) percent, alcohol + - to 8 per cent, nitric 

 acid, or chrom-acetic mixture were used. For histological preparations strong 

 Flemming's fluid or Mayer's picro-nitric mixture was used. Sublimate, with or 

 without acetic acid, gave good results. Cilia were well preserved by 10 per cent, 

 formol in sea water for lU minutes followed by one of the above named fixing 



