PUTNAM ON P0LVINARIA INNUMERABILIS. 327 



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breaking up into parts placed end to end, which were subsequently in 

 some unknown manner developed into these oval bodies. It is however 

 very ditKcult to trace any such connection, and Dr. Mark informs me 

 that Leydig has observed t'lese bodies in adult females of Lecaniuin and 

 regards them as parasitic, bearing some relation to the Pseudo-navicellce. 

 At the present moment I am not inclined to object to this view. 



Fifth. Sperical bodies from 10 // to 3u /^ in diameter (tig. 3) having a 

 specitic gravity greater than water, and composed of a number of clear 

 globules or cells inclosed in a mass of clear apparently homogeneous 

 substance which stains readily with eosene and magenta, while the clear 

 «ells remain unstained. With iodine the whole becomes stained brown. 

 In water the enveloping substance becomes more or less softened allow- 

 ing the clear cells to gradually approach the surface and finally escape, 

 after which they cannot be distinguished from the fat or food globules 

 nlready mentioned, and like them have a specific gravity less than water. 

 There is scarcely a doubt that these are immature ovicapsules, whose 

 enveloping membrane is yet unformed or so tender as to be easily rup- 

 tured. The larger individuals show evidences of their previous attach- 

 ment at one end. From an examination of the ovaries of Lecanium hes- 

 peridum it appears that these bodies are formed in the anterior portion 

 of the ovary, first appearing as simple very minute cells imbedded in a 

 tissue of fibrous appearance. The cells are quite indistinct at the ante- 

 rior end, but become gradually larger and better defined posteriorly until 

 they become comparatively free from the investing tissue.* 



Of these five classes of bodies it is probable that only the last belong 

 •exclusively to the ovaries, and, unless I am greatly mistaken as to their 

 character, each one of these spherical bodies is capable under favorable 

 circumstances of forming an egg, being in fact a true egg follicle or ovi- 

 capsule, comparable possibly to the ovule of the higher animals. 



DEVEIiOPMENT OF THE EGG, 



During the winter the ovicapsules appear to remain in the form and 

 ■condition just described, but with the advancing warmth of spring, and 

 ■consequent abundant flow of sap in the trees the development of the 

 •eggs proceeds with great rapidity. The more advanced ovicapsules are 

 now seen to be slightly elongated at one end into a short pedicle by 

 which they are attached, and to be arranged in groups radiating about a 

 •common center (fig. 5,a). The capsules develope unequally, or rather 

 progressively, so that at a later stage capsules in all stages of develop- 

 ment may be seen in the same cluster at the same time (fig. 5,6) present- 

 ing a very bud-like appearance. As the females begin to lay eggs about 

 May 24th and continue often until about July 12th, during the whole of 

 which period they may be found in all stages of development, an excel- 

 lent opportunity is afforded for the study of their formation. 



* In this specimen of L..hesperidum, examined Nov. 4th, 1878, the same membrane which 

 inclosed these spherical bodies was still connected with a cluster of eggs containing embryos 

 iu various stages of development, some of them just ready to be hatched. Whether each 

 ■ivary has only one, or more, of these anterior ends or ovarioles I did not observe. 



