354 JULIA ELEANOR MOODY 



point until the transfer is made. A method was finally suggested 

 which entirely removed this difficulty. A small quantity of 

 soft paraffin in a watch-glass was melted over the water bath. 

 By means of a capillary pipette, the specimens, either individu- 

 ally or en masse, were transferred from the xylol to the melted 

 paraffin. When a film hacl formed over the surface of the paraffin, 

 the dish was dropped into cold water. The imbedded Spathidia, 

 stained bright red, were readily located with the aid of the bino- 

 cular. Having melted with a warm needle the paraffin sur- 

 rounding the specimen, it was transferred to a glass slide which 

 had been previously smeared with dilute glycerine. From a 

 pipette of large bore, melted hard paraffin, sufficient to form 

 a good sized drop or sphere, was squeezed upon it. The hot 

 paraffin melts at once the congealed soft paraffin adhering to 

 the specimen and thus embeds it in a homogeneous matrix. 

 The sections were cut 3| microns thick and stained with iron 

 haemotoxylin. 



3. Morphology and physiology 



Spathidium spathula, as Maupas describes it, is a slender 

 flask-shaped ciliate, the rounded distended posterior end of 

 which is drawn out anteriorly to form a long greatly compressed 

 neck, obliquely truncated at the tip (fig. 1). The records of 

 Dujardin and Maupas show a great variation in the size of the 

 organism, the former quoting ISO^u to 240^ as the ordinary length, 

 while Maupas gives 160^ as the outside limit. Of fifty indi- 

 viduals measured, I found the average length and width to be 

 110.5m and 35. 2^ respectively; the smallest measuring 73, 5^ in 

 length with a diameter of ^1 ; the largest 157.5/i in length and 

 57.5m in diameter. 



Maupas described the body as capable of great extension, 

 having often observed it stretched to five or six times its normal 

 length. In swimming, Spathidium sometimes becomes entangled 

 in the zooglea at the bottom of the culture dish and under such 

 conditions it often becomes greatly extended in its efforts to 

 escape, but I have never seen it more than double its length 

 and that only on one occasion. 



