OEGANS OF EEPRODUCTION. 211 



surface of the macula, forming a projection, and, 

 indeed, sometimes appears to detach itself altogether 

 from the macula. It is always quite clear and trans- 

 parent, while the macula itself is turbid, though at this 

 stage it again contains a clear space in its interior. I 

 examined the Purkinjean vesicles of six full-grown 

 eggs, but was unable to satisfy myself as to the normal 

 state of their contents at this stage. All of them con- 

 tained the large maculae, which in some of them had the 

 form of a hollow cap. Two of them had a second clear 

 macula, about half as large as the first ; and one con- 

 tained a number of small vesicles. These changes may 

 be compared with those which I have described as 

 occurring in Geopliilus} 



The yelk consisted, as usual, of a viscid substance, 

 containing fine granules and oil-globules, varying up 

 to ^ QQ q th of an inch in diameter. Acetic acid acted 

 in the usual manner on these tissues, and dissolved all 

 the granules contained in the free nuclei (which I sup- 

 posed to be embryonic Purkinjean vesicles), just as it 

 does the true maculae. 



Dilute ammonia also dissolves the macula and the 

 granules of tbe free nuclei. 



The ovaries of L&pisma resemble those of MachUis. 

 The testes of Lepisma" are short cylindrical bodies, 

 opening by narrow vasa deferentia into one common, 

 rather wide duct on each side. There are also two 

 saccular, glandular organs, which lie one on each side 

 of the middle line, between the sperm ducts, into 

 which they apparently open, close to the external 

 orifice. 



CAMPODEADiE. 



Body elongated, cylindrical. Antennae multiarticu- 

 late. The first seven abdominal segments bear a pair 

 of appendages on the under surface. Caudal appen- 

 dages long, multiarticulate. 



1 ' Phil. Trans.,' 1861. 



2 ' Treviranus,' 1. c, p. 16. 



