176 



HARDWICKE'S SCIENCE-GOSSIP. 



virescens (Jeff.) ; Paludina vivipara, vars. unicolor 

 (Jeff.), atro-fitrpurea (Lloyd), albida (Nelson and 

 Taylor) ; Bithynia ientaculata, vars. albida (Rimmer), 

 rufescens (Ckl.), fulva (Locard), cornea (Locard) ; 

 Bithyiiia Leachii, var. albida (Rimmer) ; Valvata pis- 

 cinalis, var. albina (Taylor) ; Valvata cristata, var. 

 alba (Rowe) ; Plajiorbis lincatus, var. albina (Taylor) ; 

 Planorbis nitidits, var. albida (Nelson) ; Planorbis 

 spirorbis, yar. albida (Nelson) ; Planorbis carina tus, 

 var. albida (Hudson) ; Planorbis nmbilicatus, var. 

 albina (Jeff.) ; Pla7iorbis corneus, var. albina (Jeff.), 

 albinos (M.oc[.),ferriiginm (Pasc.) ; Planorbis contortus, 

 var. albida (Jeff.); Physa Jiypnortim, var. cuprclla 

 (Rowe); Physa fontinalis, var. albina (Jeff.); and 

 the various other unicolorous named varieties that 

 have been described. 



It is a sign of the degeneracy of the times of variety- 

 naming that there is a proneness on the part of some 

 to give definite names to the variation in the body- 

 colour of molluscs ; to me this resembles a collector 

 of plants, withal a bad botanist, who strove to render 

 aid to science by naming in latinised form the various 

 colour shades to be found in leaves of the ground ivy. 



To postulate C belong : — Physa hvpnornm, var, 

 roseolabiata (Pascal) ; Limncra stagnalis, var. roseola- 

 biata (Sturm.) ; Limntta palustris, var. j-oseolabiata 

 (Jeff.) ; Helix ncmoralis, vars. luteolabiata (Ckl.), 

 albolabiata (v. Martens), roseolabiata (Taylor), biinar- 

 ginata (Moq. ) ; ITelix hortensis, vars. roseolabiata 

 (Taylor), /nscolabiata (v. Martens), luteolabiata (Ckl.) ; 

 Helix arbustoruin, var. roseolabiata (Roberts) ; and 

 so on. 



To postulate D belong such as SphcBriuin cornenni, 

 var. compressa (Gray) ; Sphcvriiim rivicola, var. com- 

 pressa (Pasc.) ; Paludina vivipara, var. injlata 

 (Locard) ; Bithynia tentacidata, var. angulata 

 (Roberts), and the various decollated monstrosities 

 termed separately in latinised form as m. decollatuin. 



To postulate E belong such as the named parti- 

 coloured variations of the slugs and the helices. 



To postulate F belong such as Pisidiuvi fontinale, 

 var. Henslowana (Shepp.) ; Anodonta cygnea, var. 

 rostrata (Ziegl.) ; Liinmea peregra, vars. Burjietti 

 (Alder) and stagnaliformis (Taylor), with others, etc. 



So that of all the named varieties it is only those 

 that can be placed under the category of the postulates 

 E and F that I would keep as valuable aids to 

 scientific expression. In the following parts it will 

 be my aim to show that the cause of variation must 

 be sought in the plastic nature of the ovum and the 

 spermatozoon, and not by variety-naming or by mere 

 getting together locality collections of varieties, 



( To be concluded.) 



We have received Nos, i and 2 of the first volume 

 of "The Optical Magic Lantern Journal and Photo- 

 graphic Enlarger,'' and judging from these numbers 

 the journal will supply a want. 



NOTES IN ECONOMIC BOTANY. 



NUX VOMICA. — This most energetic poison is 

 the produce of a plant belonging to the family 

 Loganiacece, named by LinnKus Strychnos Nux 

 vomica. It is a native of the Indian Archipelago 

 and Peninsula, as well as the southern part of the 

 Bengal Presidency. It grows to a moderate-sized 

 tree, with a short crooked trunk ; branches irregular, 

 covered with smooth dark-grey bark ; wood white, 

 intensely bitter. Leaves opposite, oval, pointed, 

 3-5 nerved, varying in size. P"lowers small in termi- 

 nal corymbs, greenish-white. Fruit round, about 



Fig. 117. — Strychnos Xux vomica, a, flower; b, seed. 



the size of an orange, filled with a soft, white, gela- 

 tinous pulp, in which the seeds are immersed attached 

 to a central placenta. Seeds round, or shield-like, 

 depressed on one side, convex on the other, about 

 ^ inch broad, and two lines thick, thickly covered 

 with silky, ash-coloured hairs. They have little 

 smell, but an intensely bitter taste, which is due to the 

 presence of two most energetic poisons, viz., strychnia 

 and brucia, united with a peculiar acid known as 

 strychnia acid. Besides these substances the seeds 

 contain a yellow colouring matter, a concrete oil, 

 gum, starch, bassorine, and a small quantity of wax. 



