108 



Journal of Applied Microscopy. 



than those of the plumose glands, and 

 the nuclei are in or near the base of the 

 cells. Thinking that what I found in the 

 meadow lark might not be true of other 

 birds, quite a number were examined, 

 representing four different orders which 

 embraced quite a variety of food habits. 

 Of Passeres, meadow lark, English spar- 

 row, blue jay, crow and Tennessee warb- 

 ler were studied. Two of Picariae were 

 taken, the red-headed woodpecker and 

 chimney-swift. In Gallmar, the domes- 

 tic chicken, and in Raptores the spar- 

 rowhawk were examined. In all these, 

 the structure was identical, consisting 

 of a series of plumose glands, each with 

 a large number of tubular acini, and 

 around the duct of these glands a series 

 of tubular glands. In the small birds, 

 these glands were set nearly at right 

 angles to the organ, but in the larger 

 birds, they were set obliquely. 



As to the nature of these different 

 glands, I am of the opinion that the 

 plumose glands are peptic and the tubu- 

 lar are mucous. If any one will take the 

 trouble to prepare sections of this organ 

 in any bird, say of the size of the blue 

 jay, as that is the most convenient size 

 for study, and compare the cells of the 

 plumose glands with the cells from the 

 stomach of a rabbit or cat, or with the 

 pictures of the peptic cells of the human 

 stomach, one will see the resemblance. 

 The cells of the tubular glands bear a 

 close resemblance also to the mucous 

 cells of the same organs. In order to 

 see these properly, they should be 

 double-stained with picro-carmin or 

 haematoxylin and borax carmin. 



G. H. French. 

 Carbondale, III. 



APPARATUS. 



Thermo-regulated Waterbaths for 

 the Bacteriological Laboratory. 



There is, perhaps, a no more useful 

 piece of apparatus in a general bacteri- 

 ological laboratory than a suitable 

 thermo-regulated water bath. The uses 

 to which it may be advantageously put 

 are so numerous that after the habit of 

 using it is established it soon becomes 

 almost indispensable. Wiesnegg antici- 

 pated its value and placed upon the 

 market his bain-marie which has met 

 with unquestioned favor. However, its 

 usefulness, on account of its form and 

 size, is somewhat restricted. In order 

 to extend the utility of the principle 

 involved in this apparatus, I have had, 

 by way of experiment, two water baths 

 or tanks constructed and permanently 

 fitted with thermostats and thermom- 



eters. They have been in use for nearly 

 a year and have proven to be so satisfac- 

 tory that a brief note concerning them 

 may be of general interest. Their shape 

 or size should not be taken into serious 

 consideration, for they are flexible 

 features which can easily be adapted to 

 individual needs or requirements. The 

 emphasis should be placed rather on the 

 assistance they render in the saving of 

 time and in the securing of uniform 

 results. In laboratories where instruc- 

 tion is given such assistance is much 

 appreciated by both students and 

 instructors. 



Fig. 1. 



The larger water bath (Fig. 1) to which 

 a therm.ostat was connected is of special' 

 value in macerating meat at a high 

 (60-65° C.) temperature for making cul- 

 ture media._ It can also be used for a 

 variety of other purposes, such, for 

 example, as sterilizing liquid blood 

 serum or by a class of laboratory stu- 

 dents in determining the approximate 

 thermal death points of different bac- 

 teria. It consists of a rectangular copper 

 tank 45x50x25 centimeters. It is divided 

 into two apartments, each of which has 

 a separate cover and perforated false 

 bottom. The partition consists simply 

 of a top crosspiece which is about four 

 centimeters wide. Near its center is a 

 round opening two centimeters in diam- 

 eter for a thermometer, which is protect- 

 ed by a perforated copper tube extending 

 to and soldered to the bottom of the 

 tank. Near the end of the crosspiece, or 

 close to the side of the tank, there is a 

 second and similar opening and shield 

 for a thermostat. There is a faucet for 

 drawing off the water. The tank stands 

 on an iron quadruped. For heating it 

 has been found desirable to use two 

 burners, one under the middle of each 

 side or apartment, the burners being 

 connected by means of a T or Y tube 

 to the gas tube leading from the 

 regulator. 



