Page:The Zoologist, 4th series, vol 2 (1898).djvu/223

Rh Dabchick (Podicipes fluviatilis). St. James's Park.— (3, Harcourt Buildings, Temple).

Yarrell's Blenny and the Two-spotted Goby at Scarborough.—While poking about in the rock-pools in the South Bay, Scarborough, last July, I captured two small fishes, with which I was unacquainted, I sent them to Dr. Günther, who kindly named them for me as Yarrell's Blenny (Carelophus ascanii), and the Two-spotted Goby (Gobius ruthensparri). Both species, he says, are not very common, and are somewhat local. Since then I have seen two otber specimens of the former, but have not succeeded in finding any more of the latter.— (44, Huntriss Row, Scarborough).

Abnormal Scalariformity in Shells.—In August, 1893, whilst examining the dykes at Pevensey, I came to a spot where the weeds were particularly dense, and here met with an irregularly scalariform shell (immature) of Planorbis complanatus, and another regularly scalariform specimen of P. vortex var. compressa (Mich.), both being dead shells. Having examined tbese closely, and mentally ruminated as to the probable cause of this kind of deformity, I drew a decided conclusion that the animal from some cause or other—possibly a deformity or a wart at the back of the head—was induced to direct the head downwards, in which case the shell-whorls would be formed at an angle. Being impressed with this idea, and hoping to obtain a living specimen, I went again to the same place, and obtained another similar specimen of P. complanatus, alive. On examining it with a one-inch objective (which I always use as a pocket-lens), I saw distinctly several minute white worms attached exactly where I had expected to find the causa mali, that is to say, on the head between and around the tentacles. They attached themselves by the hinder portion of their bodies, the front part being free and waving about, as if on the look-out for anything in the shape of food. The action was exactly similar to that of a caterpillar, and they looped their bodies similarly also. The lip of the shell evidently formed a capital shelter, from under which they could protrude or withdraw their bodies. On examining one of the worms under the microscope—for they were rather minute, perhaps a line or so in length—I found that the setæ were placed more on the ventral surface than usual, and that they occupied only the posterior half of the animal, with the exception of a pair of oral tufts, which were directed forward. There were some seven pairs of bristle-tufts in the hind portion of the body, and an average of ten bristles in each tuft, making 140 bristles in all. With a quarter-inch objective it could be seen that each bristle was terminated by a double hook