HA R D WICKE ' S SCIENCE-GOSSIP. 



A DOUBTFUL SPECIES OF THE GENUS 

 CECISTES. 



Sf>. Ch. — Corona small reniform, with a wide dorsal 

 gap ; body long and slender ; foot long, ex- 

 tensile, tapering, and markedly wrinkled ; ven- 

 tral antenna a small setigerous tubercule ; hook?, 

 two dorsal, prominent, adnate at the base ; tube 

 floccose inconspicuous, or absent. 



THE corona is small, slightly larger than the 

 widest diameter of the body, and although in 

 a side view apparently circular, is really reniform by 

 the inbending of a wide dorsal gap. This latter is 

 occupied when the corona is expanded by the tips of 

 two large hooks, adnate at the base, which are 

 prominent features when the Rotiferon is contracted. 

 The body is slender and cylindrical, with patches of 

 minute yellow granules at and near the junction with 

 the foot. The ventral antenna is a setigerous pimple 

 seated upon a small prominence, the upper surface of 

 which is ciliated. The buccal orifice is lateral and 

 strongly ciliated, sloping downward, but slightly in a 

 dorsal direction, at the bottom two lip-like projec- 

 tions constantly open and shut, as if in the act of 

 biting, but occasionally with a quick, upward jerk 

 throw away some undesired morsel. The mastax in 

 dorsal view is trilobate, enveloping the semi-globular 

 trophi, whose teeth are three in number, and 

 seemingly parallel. A long slender oesophagus, 

 which is thrown into waves when the creature is 

 feeding, leads to a thick walled, capacious stomach, 

 filling the larger part of the body cavity ; a marked 

 constriction divides it from the intestine ; gradually 

 narrowing into a long rectum, it bends in an upward 

 direction to the cloaca. The latter is bounded on 

 either side by wart-like projections which become 

 greatly distended in the act of passing fasces. The 

 ovary frequently contains a large egg, more or less 

 fully formed, while others are embedded in the 

 flocculent mass that does duty for a case. The foot 

 is tapering, deeply transversely wrinkled, and very 

 extensile ; although not usually much longer than the 

 body, occasionally it is stretched to fully two and a 

 half times its length, and even then its corrugations 

 are not appreciably smoothed out. Two muscular 

 threads run from one end to the other, and near the 

 junction with the trunk appear to pass through two 

 thick swellings that may be the foot-glands. The 

 case as a rule consists of an irregular accumulation of 

 debris, hiding the base of the foot and quite in- 

 adequate as a protection ; but even this is sometimes 

 entirely dispensed with. In one instance, however, 

 a pair were inhabiting a transparent gelatinous case 

 only rendered visible by the particles of dirt adhering 

 to it, and into which they retreated on alarm. It 

 was more like the case that one sees occasionally 

 investing a stentor, and I am not at all sure that they 

 had not taken advantage of the empty dwelling of 



something else. In habit they are! quiet, extremely 

 timid, contracting at the slightest [tap, but equally 



7 



Fig. 77. — CEcistes, extended. 



ready to expand again. Their favourite position is 

 in the axils of the leaves and stems. 



I first came across this Rotifer on the 19th of April, 



