292 KANSAS UNIVERSITY SCIENCE BULLETIN. 



creeping over the rough surface of the appendage, but also 

 serves as an efficient means of attachment. Near the oral 

 opening protrudes a long flagellum which lashes rapidly to and 

 fro and secures food for the animal. 



The small visitor thus established on the appendage of a 

 barnacle obtains its food from the currents of water which are 

 constantly coming in to the host. When the dangers come and 

 the appendages are enclosed by the calcareous plates of the 

 barnacle, the ciliate still has moisture and some food. One 

 might think that in casting its lot with a sedentary animal the 

 free-swimming protozoon had limited its opportunities. This 

 is not wholly true. Lepas pectinata grows on masses of lava, 

 and during storm these masses become broken and widely 

 scattered. It is only occasionally that the Naples collectors are 

 able to find this barnacle — its appearance in the bay depend- 

 ing upon, first, a storm at sea, and then a strong south wind to 

 sweep it in. During April and part of May I was able to ob- 

 tain this material but twice. This was unfortunate as the 

 nucleus is an interesting one, and promises well for cytological 

 work. The barnacles live less than a week indoors and the 

 ciliates perish with them. Moreover, the ciliates are not nu- 

 merous. As a last resort for material^ I took barnacles from 

 the storeroom, preserved in formalin, and succeeded in find- 

 ing the specimens, but they did not prove satisfactory for 

 nuclear study. 



DESCRIPTION OF SPECIMEN. 



The animal is oval in form, being slightly wider cephalically. 

 It is covered with siliceous skeleton, giving the appearance of 

 a bivalve shell, and possesses a caudal appendage. So differ- 

 ent is it from the usual infusor that it is little wonder most 

 zoologists at first glance pronounce it a rotifer, or a mollusk, or 

 a low crustacean. The animal is flattened dorso-ventrally, the 

 dorsal shell being more extensive and bending over the right 

 side. The dorsal is slightly convex ; the ventral is concave and 

 attaches to the dorsal by a deep groove on the left. The right 

 edge of the dorsal shell and the left edge of the ventral do not 

 meet, thus leaving exposed a very narrow strip of protoplasm. 

 This uncovered protoplasm is ciliated and it is by means of 

 these cilia that the animal swims. The surface of both shells 

 is smooth. 



The crevice between the ventral and dorsal plate lies then 



