A. H. H. LATTEY, OBSERVATIONS ON THE POLYZOA. O 



equally delicate animals, the Halodactylus for instance, are unpro- 

 vided with any such protection. Others suppose that they are 

 destined to entrap the passing animals, and hold them in their firm 

 grip until decomposition has diffused them in the surrounding 

 water, thus furnishing the creatures with a supply of nourishment ; 

 this, to my mind, appears the most feasible explanation. I have 

 found these animals in great abundance at Ilfracombe, especially upon 

 the rocks near the harbour, mostly depending from their under sur- 

 face ; the Campanularia Dichotoma in the same locality on the leaves 

 of brown sea-weeds, and the Sertulari^ growing from the sides of 

 rock pools at St, Leonards and Exmouth. The Halodactylus may be 

 found in any locality where there are rocks, encrusting the stems and 

 fronds of the common bladder wrack (fucus vesiculosus) at low 

 water, especially during spring tides. It looks like a firm gela- 

 tinous coating of a brown colour, and has a semi-transparent 

 appearance. When put into fresh sea water, it is seen to be- 

 come gradually, as the animals emerge from their cells, overspread 

 with what appears, to the naked eye, to be a minute white downy 

 covering. 



If it is desired to make preparations of any of these creatures, 

 the following will be found a successful plan. Their extreme sensi- 

 tiveness, and the rapidity with which they withdraw themselves 

 into their cells upon the slightest touch or jar, makes it necessary 

 to adopt a peculiar plan of proceeding. I would premise that 

 before commencing operations with the Halodactylus it is desirable 

 to cut it into the length required to fit the cell in which it is to be 

 placed whilst the animal is contracted, as it may then be cut in any 

 direction without injury, but when expanded it requires to be very 

 carefully handled, as if the bells are in any way pressed or put out of 

 shape they cannot be restored. For this reason it should be so cut 

 as to fit the cell tightly so as to prevent its being shifted. The 

 object is to coax the animals out of their tiny homes, and to keep 

 them out until you can kill them. To accomplish the first object, 

 it is best to keep them out of the water for several hours, and then 

 to put them into fresh sea-water in any appropriate vessel. I have 

 found a circular glass dish, such as is used for cakes of trans- 

 parent soap, answer very well, as it can be put upon the stage of 

 the microscope, and the effects of different stages of the operations 

 watched, which is of importance. Some alcoholic spirit mii«t 

 now be added very gradually — spirit of wine, brandy, whisky, or gin. 



