178 Excursion to Burnley Quarries. [vd *^xxxTii 



numbers, and proved an object of interest to some of those 

 present. Portions of the water plant Myriophyllum were next 

 collected, as it generally proves to be the home of numerous 

 Protozoa and Rotifera, and subsequent examination under 

 the microscope proved it to be so in this case also. Casts with 

 the net produced a fair number of Entomostraca, minute 

 crustacean forms. A move was finally made to the excavation 

 at the north-west end of the quarries, where free -swimming 

 rotifers are generally fairly plentiful, but the reverse proved 

 to be the case on this occasion. The green colour of the 

 water, however, suggested the presence of minute vegetable 

 organisms, which were later found in large numbers in the 

 material collected, together with green Protozoa of the Euglena 

 type. Of the Protozoa taken during the afternoon, two were 

 worthy of special mention, both being allied to the common 

 Vorticellae. One of these was Thiiricola operculata, a tiny 

 creature which constructs a vase-like tube in which it hves. 

 As a special defence against interlopers, it fits a door to its 

 residence, which opens outward only, and which closes down 

 immediately the animal retracts. The other protozoan referred 

 to was a Pyxicola, which resembles P. socialis more nearly than 

 any other ; but as this is described as a marine form, and social 

 in its habit, if the two be identical, that taken must have 

 altered both its habit and its habitat. This particular speck 

 of animated matter, about 1/250 inch in length only, also builds 

 an urn-shaped residence. The animal is furnished with a sort 

 of pad on one side at its outer end, which acts as a stopper 

 to its tube when it retires within its abode for safety. Diatoms 

 were found to be extraordinarily numerous, but not many 

 species were represented, the most noteworthy being Bacillaria 

 paradoxa, which exhibits most remarkable power of move- 

 ment, and that of a most mysterious kind, making it an object 

 of special interest to the microscopist. Although the weather 

 was rather showery, it is hoped that some, at any rate, of those 

 present were satisfied with their outing. 



The following is a list of the captures : — 



Algae. — Enteromorpha {? intestinalis), Monostroma (? membrair 

 acea. West), Bacillaria paradoxa, Navicula, sp., Surirella, sp. 



Protozoa. — Arcella vulgaris, Actinophrys sol, Anthophysa 

 vegetans, Euglena viridis (?), Opercularia (?), Tharicola operculata, 

 Pyxicola (? socialis), Vaginicola, sp., Stentor. sp., Vorticella 

 campanula, Stylonichia mytilus. 



Coelenterata. — Cordylophora, sp. 



Worms. — ^The rotifers (Ecistes (Ptygura, Ehr.), sp., Anuroea 

 (Keratella), sp. 



