INDUSTRIAL PROGRESS DURING THE YEAR 1875. clxxix 



Professor Allman has given in his anniversary address to 

 'the Linnsean Society a sketch of "Recent Progress in our 

 Knowledge of the Ciliate Infusoria." The same thina: in 

 briefer space has been attempted by Dr. Packard in the 

 American Naturalist for all the Protozoa, especial stress 

 being laid on their modes of reproduction. 



Further studies on the Gregarince have been made by A. 

 Schneider. It is well known that these low Protozoa on ma- 

 turing encyst themselves and break up into a number of 

 spores (pseudonavicella3 and psorospermeaa). In two genera, 

 Gregarina and Stylorhynchus, Schneider has found a special 

 apparatus for the dissemination of these spores. 



A detailed account of our North American sponges has 

 been begun by Professor Hyatt, and it is now hoped that 

 these neglected animals may be worked up. The first paper, 

 on the North American Poritidce, has an excellent plate, and 

 contains references to certain foreign species. Mr.N. J. Car- 

 ter has published a classification of the sponges, in which the 

 orders and families, and groups within families (not genera 

 and species, however), are characterized. The fresh -water 

 Spongilla has been found by Mr. Sorby to contain constitu- 

 ents, such as varieties of chlorophyl and xanthophyll and 

 lichnoxanthine, all of which occur in plants. 



A gigantic hydroid polyp was dredged by the Challen- 

 ger Expedition, measuring seven feet four inches high, and 

 the crown of tentacles nine inches across from tip to tip of 

 the exj^anded (non-retractile) tentacles. It occurred at the 

 depth of 1875 fathoms, on the 17th of June, in latitude 34 

 37' north and longitude 140 32' west, and again, four feet 

 in height, at the enormous depth of four statute miles, on 

 the 5th of July, in latitude 37 41' north and longitude 177 

 4' west. The stem is enormously extensile, of a pale pink 

 color. It is either a species of Monocaulus or an allied form. 

 The proximal range of tentacles number about a hundred, and 

 these are about four inches long, and almost transparent 

 in life. The ovisacs are in close tufts of a maroon color, 

 just at the base of the proximal tentacles. " The walls of 

 the body-cavity," writes Professor Wyville Thompson, " were 

 yellowish, and seemed to contain some vertical rolls of gran- 

 ular matter, and the hypostome terminates in a fringe of 

 about forty - eight or fifty extensile tentacles around the 



