158 OX OLANDS rft THE MMXILL.E OF TEGE5A.EIA. 



Fig. 5. 



■ • • • m 9 * 

 • • ® «*®o« • • • • • 



as"® 



a ® 



• ••/ 



Diagrams representing the gland-openings on the maxilla of Tegenaria 



domestica at different stages ; about X 200. 



A. As in the exuvium of right maxilla, 15th May. B. Ditto, 9th June. 



0. Ditto, 1st August. D. Ditto, 21st September. E. As in the exuvium of left 



maxilla, 1st August : the integumentary channels are here shown. F. As in 



exuvium of 21st September. G. Gland-openings in an adult female of T. do- 



necessarily prolonged, owing to the continual rupture of the duct 

 and terminal portion of the glands' 'on opening the maxillae. I 

 first observed the external organs with a f objective, and think 

 that the reason why they have hitherto escaped notice is that 

 under such a low power they appear like simple rings, and 

 resemble the integumental structure at the base of some minute 

 setae distributed about the same surface. Even with a \ and 

 r \j- this definition might at first be confirmed, and the form 

 of the raised disk attributed to the approximate focusing of 

 different points in an attached open duct. By using the bleach- 

 ing process described by Dr. Braxton Hicks (Linn. Trans. 1st ser. 

 vol. xxii. p. 396) and mounting in balsam, the form of the external 

 organ, however, is clearly seen with a \ objective. 



