FEiMALE ORGANS OF GENERATION. 185 



Such ovaries are found in Ephemera and Stratiomys. Muller 

 calls this form bunches of ovaries (ovaria racemosa *), and supposes 

 that the exterior., tunic of the bag, or properly the bag itself, is 

 wanting, the eggs being connected together by means of air-vessels ; 

 but Swammerdam's figure misled him f. In a female of Ephemera 

 marginata, Fab., De Geer, which I dissected, I clearly observed the 

 exterior tunic, the ova were contained within it, egg being linked to 

 egg by a delicate filament. In Stratiomys also Swammerdam has dis- 

 tinctly represented the bag]:}:. 



II. The short ovaries, which contain but few germs, are placed 

 longitudinally upon a large, bag-shaped, common ovarium. 



There are many subordinate_differences of this peculiar form, which 

 we will briefly indicate. 



1. OVARIA PECTINATA (PL XXVII. f. 2.) are short egg tubes, 

 which contain but few germs, and are placed in a row upon the upper 

 side of a common duct ( Mantodea). 



2. OVARIA ECHINATA, common egg ducts, long, broad, wider ante- 

 riorly and suddenly pointed, having beneath many very small scale- 

 shaped egg tubes, which lie over each other (dragon flies). 



3. OVARIA IMBRICATA (PL XXVII. f. 8.). The whole upper sur- 

 face, with the exception of a narrow edge upon the lower margin, is 

 covered with short tile-shaped egg-tubes, which lie upon each other, 

 and embrace the intestine like a roof. Each tube contains a large 

 developed egg and behind it the minute germs of two or three others 

 (grasshoppers, crickets, Phryganea, Sialis, Tipula, Sirex, &c.). 



4. OVARIA BACCATA. The common ovarium is a bladder or tube 

 upon the entire upper surface of which are placed the short egg-tubes, 

 generally containing but few eggs, (Coleoptera vesicifica, each tube 

 with from one to four eggs; Semblis, each with six to nine eggs). 



5. OVARIA DICHOTOMA (PL XXVII. f. 5. ovaria fur cata, Muller). 

 The common ovarium is forked, and upon each prong, and particularly 

 upon their opposite sides, there are many tubes, containing but few (3) 

 egg germs (Gryllotalpa). 



6. OVARIA RAMOSA (PL XXVII. f. 6.). The common egg duct 

 does not simply furcate, but several branches are given off one after 

 the other, each of which contains some egg germs (Lepisma). 



* Nova Acta Phys. Med. p. 601. 11. f Bib. Naturae, PI. XXV. f. 1. 



Ib.Pl. XL VIII. f. 1. 



