30G ]\Ir. T. D. A. (^ockcixll — Descriptions and 



!My knowledge of tlie habits of our marine Mcdusfc leads 

 me to believe that Limnocnida has a hydroid stage in its 

 life-history. So far as I am able to foresee^ there should be 

 no great difficulties to be overcome in rearing the fertilized 

 ova of Limnocnida in small bell-jars. It would be a much 

 quicker method than that of trying to find the hydroid in the 

 lakes. The hydroid may have a special habitat which might 

 take many year.s to find. If, on the other hand, the Medusa 

 reproduces by direct development only, one would be able by 

 1 earing the ova to observe and preserve all the stages. 



Limnocnida still remains outside any system of classifica- 

 tion. It looks at first sight a Narcomedusa, on account of 

 the shape of the stomach and the position of the gonads; 

 but I do not think that it has any connexion whatever with 

 the Karcomcdusfe. Whether it is an Anthomedusa or is 

 closely related to the Anthomedusse should be decided when 

 its development and life-history are definitely and clearly 

 known. At present I am inclined to look upon Limnocnida 

 as a specialized Anthomedusa. I have jiromised to give a 

 description, with figures, of the specimens from the Niger in 

 the " Budgett Memorial Volume.'^ 



Boferences. 



(i) GuF.ENE, JvLES DE. 1894. "On a Medusa observed by Dr. 

 Tautain in the Eiver Niger at Bamakou (French Soudan)." 

 Ann. & ]\Jag. Nat. Hist. ser. 6, vol. xiv. pp. 29-34. 



(2) GvKTHER, li. T. 1893. " Preliminary Account of the Fresh- 

 water Medusa of Lake Tanganyika (L/mnocnida tanyanicce)." 

 Ann. & Mag. Nat. Hist. ser. 6, vol. xi. pp. 269-:i75, pis. xiii. 

 & xiv. 



{3) Geavier, C. 1903. "Sur la MMuse du Victoria Nyanza." 

 Couiptes rendus Acad. Sci. Paris, torn, cxxxvii. pp. 867-869. 



5th February, 1906. 



XL. — Descriptions and Records of Bees. — IX. 

 By T. D. A. CocKERELL, University of Colorado. 



Andrena {Trachandrena) perforatella, sp. n. 



5 . — Length about 8 mm. 



Black, with the middle and hind tarsi, and the hind tibise, 

 clear red ; pubescence greyish white, the hair at apex of 

 abdomen golden ; wings strongly yelloMish_, the stigma and 

 nervures clear ferruginous ; flagellum dusky reddish beneath. 

 Process of labrum very broad, truncate; clypeus exceedingly 

 densely punctured, with no smooth line ; facial foveie, seen 



