Fnrtlier Observations on Koeuenia. 407 



poured from the bottle into a stender-disli in tlie laboratory the 

 Koenenia remained floating and were tlien g^ently picked up with a 

 briish and placed in a g-lass cell by the side of a piece of raoist 

 lilter paper. whicli was then covered over. With a number eight 

 ocular and a three objective they could be observed to great advantage 

 as they ran around. Often they would become quiet and remain so 

 for an hour, tlnis enabling- one to use the camera lucida in sketching 

 them. When the aninial was quiet for a long- time there was no 

 trace of life save a slight peristaltic movement of the intestine 

 (while even this sometimes ceased), and a rythmic-pnlsation on either 

 side of the head near the origin of the second pair of appendages, 

 or pedipalps. 



Just what is tlie function of these pulsating bodies I am unable 

 to say. They are in the region of and seem to be surrounded by 

 the coxal glands. Sections through this region reveal alniost nothing, 

 so delicate is tlie tissue which is found there. In some of the living 

 speeimens examined, no clear line of deraarcation could be made out 

 between this pulsating area and the thoracic diverticula of the in- 

 testine, while in other regions the digestive tract stood out in great 

 clearness and we were able to see particles churning around in its 

 yellowish* confines. I have followed with my eye food particles in 

 their course from the thoracic diverticula, through the straight course 

 of the intestine into the abdomen, where they were sent into first 

 one and then another of the abdominal diverticula. These diverticula, 

 it seems, vary in number as well as in size, for the anterior pair is 

 sometimes absent or it is sometimes represented by one diverticulum 

 and not by a pair. The camera sketch that I made of a female 

 Koenenia shows this condition of the digestive tract. The ovary in 

 the same specimen showed up large and clear. The sketch in which 

 this Organ is shown brings out the longitudinal furrow on the ventral 

 side, made by the contraction of the ventral and dorsoventral muscles. 

 j This furrowed condition was most common in the living animal of 

 both sexes. I have never seen the lung-sacs protruded in any but 

 dead speeimens. The festes do not show their paired condition in 

 the living animal, in fact, it was difflcult to make these organs out 

 jbecause of the minuteness of their structure and their failure 

 to take stains. It is only with the use of Zenker's fluid, a mixture 

 'of acetic acid, corrosive Sublimate and Müller's fluid and followed 

 iby Iron Haematoxylin and Orange G stains, that I have succeeded 

 in observing the true State of affairs. The festes are more like 



