64 BULLETIN OF THE LABORATORIES 



what Ehrenberg has called Brachionus ampiceros. Hudson and Gosse 

 consider this to be a variety of B. pala. 



Sp. 23. Brachionus urceolaris, Ehrenberg. 



Brachiomus urceolaris, Hudson and Gosse, The Rotif- 



era, or Wheel-animalcules, Vol. II, p. 118; pi. XXVII, fig. 6. 



It is not easy to decide whether the species here described is B. 

 ufceolaris or B. rubens. After some hesitation I have considered it to 

 be the former. I append a description : 



Lorica sub-quadrangular, longer than broad. Cephalo-dorsad 

 margin of the lorica bearing six straight teeth Lateral teeth largest, 

 Middle pair next in size. None of the teeth very large, the lateral 

 teeth, however, are relatively larger than the corresponding teeth of 

 the British species. Between the middle teeth there is a shallow, con- 

 cave, depression. From the base of the tooth to the bottom of this 

 depression is about as long as the height of the tooth. Cephalo ven- 

 trad margin of the lorica slightly elevated and indented at the meson. 

 Laterad margin of lorica straight, caudad margin convex. No caudal 

 spines. A sub-square orifice in the middle of the caudo-ventrad mar- 

 gin of the lorica serves for the exit of the very flexible, wrinkled, 

 foot. This orifice is bordered by two lateral papillae. 



This species is often encountered in ponds containing plant life. 

 Either this or a closely allied species is often found attached to the 

 lorica of Moina paradoxa, Weismann. 



Sp. 24. Brachionus bakeri, Ehrenberg. 



[Plate I; Figs. 1-3.] 



Brachionus bakeri, Hudson and Gosse. The Rotifera, 



or Wheel-animalcules; Vol. II, p. 120; pi. XXVII. fig. 8. 



Brachionus bakeri, C. L. Herrick, Bull. Sci Lab. of 

 Denison Univ., Vol, I, p. 55. 



This is the commonest of our Brachionidae and it is subject to 

 great variations, not only in appearance but also in size. Some varie- 

 ties appear to be fully one-third again as large as others. 



The markings upon the loriea vary in different individuals. In 

 some cases the lorica is smooth, while in others it is more or less 

 facetted and granulated. 



The shape of the depression between the middle teeth of the 

 cephalo-dorsad margin of the lorica also varies. In some individuals 

 this depression is acute, while in others it is strongly convex. 



