Experimentally Fused Larvae. 



135 



these fluids are voided while the ticks feed, and it has been sug- 

 gested that the infection is transmitted by the flowing of the fluids 

 into the wounds made by the mouth-parts of the ticks in feeding. 

 Spirochetes had not been seen in these fluids and it was suggested 

 that they existed there in a coccoid form. 



On several occasions, coxal and anal fluids, excreted by infected 

 ticks, coming from Uganda and British Central Africa, have been 

 examined. In every instance the fluid was taken while the ticks 

 fed upon an uninfected animal. The fluid collected was free 

 from blood and, in two instances, coxal fluid was collected ap- 

 parently free from anal excretion. On six occasions, after the 

 fluid had been centrifugalized, spirochetes were found in it; 

 their morphology is not distinct from that of Spirochceta duttoni. 

 Spirochaetes were found in the fluid that apparently contained no 

 anal excretion. 



88 (784) 



Experimentally fused larvae. 



By A. J. Goldfarb. 



[From the Department of Natural History, The College of the City 



of New York.] 



When the eggs of Toxopneustes variegatus were subjected to a 

 5/8 molecular NaCl, after the removal of the fertilization mem- 

 brane, considerable numbers were subsequently fused together. 

 I have counted as many as forty percentum, in the optimum 

 solutions, of agglutinated and fused pairs, triplets, etc. Few of 

 these reached the pluteus stage of development due to the early 

 death of all fusions of more than three eggs, and to the large 

 mortality of even the double embryos. 



The plutei contain at least three characteristic tissues, namely, 

 body wall, archenteron, skeleton. The first two of these behaved 

 essentially as described by Driesch in various European species, 

 and by the writer in the American species Arbacia ptmctulata; 

 i. e., the body walls or the archentera of plutei derived from 

 separate eggs were united either incompletely or so completely 

 as to give little or no evidence of the original dual character of the 

 larva?. 



