FUNGUS OCCURRING IN PULVINARIA INNUMERABILIS. 30 1 



rect in believing these to be yolk and fat globules. Third,' ex- 

 ceedingly minute, apparently spherical bodies, heavier than water 

 and staining with cosine. Putnam thought that these might be 

 bacteria although he suggests that they may be comparable to the 

 blood-disks [erythrocytes] of vertebrates or that they may be 

 stages in the development of the fourth class of bodies which he 

 next considers. That all of these suppositions are probably in- 

 correct will appear from our account on a later page. Fourth, 

 small oval bodies 3/^-5^ in diameter and io/x long and heavier 

 than water. These represent the organism which we have studied 

 but Putnam was unable to decide whether they were spermato- 

 phores or whether they corresponded to the pseudonavicella: 

 observed by Ley dig in Lccanium, as had been suggested to him 

 by Dr. E. L. Mark. 1 A fifth class of bodies observed were the 

 small incompletely formed eggs. 



There can be no doubt that Putnam found the fungus with 

 which we have worked as his description and figures make this 

 point very clear. As he found it in all cases, it is further clear 

 that the symbiont enjoys a wide range since his observations were 

 made on specimens collected in the middle west and our own on 

 material from eastern Massachusetts. 



Metschnikoff ('84) found in a crustacean, Daphnla magna, a 

 fungus which he called Monospora bicuspidata. This he re- 

 garded as a parasite, but recent developments in the study of 

 apparently similar organisms in insects, suggests that these Crus- 

 taceans should be reexamined. 



Moniez ('87) described a fungus which he called Lccaniascus 

 polymorphus, occurring in the scale insect, Lecan'mm hesperidum. 

 He refers to Leydig's 1854 paper, mentioning the fact that 

 Lecaniascus is evidently the same as Leydig's pseudonavicellae. 

 Moniez speaks of the organism as a parasite, and he found it in 

 all specimens, both young and old, of the Lccanium that he ex- 

 amined. He described the isolated cells as 4-5 ^ in length, and 

 found mycelia attaining a length of 50-60 p.. Some doubt is cast 

 upon this author's conclusions by Vejdovsky ('07) who suggests 

 that Moniez may have seen two microorganisms, one represented 



i Mark ('77) does not consider these bodies, however, in his paper on the 

 anatomy and histology of the Coccidse. 



