18 



Aquatic ILitt 



includes both viviparous and oviparous 

 species. Mr. Brind is probably right in 

 asserting that H. fluviatilis is the sole 

 viviparous fish thus far brought from the 

 East for our tanks. It is not related to 

 the viviparous killifishes. sub-family Poe- 

 ciliinae, which includes all such fishes 

 studied and bred by the aquarist. Until 

 recently these live-bearing fishes were 

 thought confined to the Americas. Mr. 

 C. Tate Regan, of the British Museum, 

 has described the remarkable Phalloste- 

 thus dunckeri, a new poeciliid and the 

 type of a new sub-family. This fish is 

 from Johore, on the Malay Peninsula. 

 While in all the forms limited to the 

 Americas, it is the anal fin which serves 

 as the so-called intromittent organ, in 

 this new species it is the ventral fins 

 which have become modified into a large 

 muscular appendage to function as the 

 intromittent organ. An interesting paper 

 on viviparous fishes in general will appear 

 in a subsequent number. Mention is made 

 of some quite curious characteristics. — 

 Editor.) 



Aquarium Heating 



(Concluded from page 16.) 

 in the concrete base, with %-inch pro- 

 jecting above to receive the glass. The 

 other parts of the frame were made of 

 34 -inch iron. Before pouring the con- 

 crete into the mould for the base several 

 inverted pie pans were placed on the bot- 

 tom angle. Through these pans the heat 

 is transmitted to the water. The pans 

 were, of course, waterproofed before 

 being used. 



No vent was made in the tray to allow 

 for draft, the cracks in the joints in the 

 wood tray being found sufficient. If 

 found necessary holes could be bored 

 through the ends. The portions of the 

 pipes shown in black in my sketches indi- 

 cate those covered with sheet asbestos 

 and taped. 



Considerable discussion has been 

 evoked at the meetings of the Aquarium 

 Society of Philadelphia by the important 

 query: "What is the best planting 

 medium in the freshwater aquarium, 

 sand, soil, grit or pebbles?" At first a 

 divergence of opinion was expressed, but 

 later experimentation led to an almost 

 unanimous concurrence in what has 

 since been adopted as the best practice. 



Some desirable plants — Sagittaria, 

 Vallisneria, Anacharis, Cabomba and 

 Nitella — will thrive and exhibit paler 

 green leaves when set directly in the 

 sand ; but other plants — Ludtvigia, Poto- 

 nwgeton, Moneywort and Water-poppy — 

 require soil to continue their growth and 

 to survive under the changed conditions. 



The best practice, it has been found, is 

 to place a two to two and one-half inch 

 layer of thoroughly washed bar or beach 

 sand in the aquarium, into which shallow 

 dishes or pots containing clean turf in 

 which the last mentioned are arranged 

 Then those to be planted directly in the 

 sand are introduced, and the whole sur- 

 face covered with a one-inch layer of 

 small beach pebbles known as grit. A 

 few larger pebbles, or brookworn stones, 

 may be scattered over the surface to pro- 

 duce a natural effect. 



Grit permits the finer particles of 

 humus to sift through to the sand layer 

 to serve as nourishment for the plants, 

 presents a neat and tidy appearance, and 

 a firm layer from which to syphon the 

 excess accumulations. — Aquarium Notes 



and Nezvs. 



-#- 



Haplochilus lineatus is the proper 

 name for the fish usually called Haplochi- 

 lus rubrostigma by the aquarist. The 

 latter is not a synonym, but the name of 

 another and distinct species with which 

 "our fish" was confused when first im- 

 ported. 



