英国学生科学读本 Lesson 31 游来游去的蛇
第31课 游来游去的蛇
Snakes belong to the class of animals which is known as reptiles. Very few snakes are found in our country. InIreland there are none at all; and in England and Scotland there are only two kinds to be met with.
蛇属于动物界里的“爬虫类”。英国的蛇非常少， 爱尔兰一条蛇也没有， 英格兰和苏格兰也只能见到两种蛇。
One of these is the common or ringed grass-snake, which is quite harmless. The other is the poisonous snake called the adder or viper.
一种是常见的“水游蛇”， 基本是没有害处的;另一种是有毒的“极北蝰”。
A full-grown viper is rather less than two feet in length. It is of a brownish-yellow colour, with a chain of black marks running in a zig-zag line down the back.
极北蝰长大以后， 也不足两英尺长。身体是棕黄色的， 背上有“之”字形的黑色条纹。
In its upper jaw it has two long hollow teeth or fangs, each of which is joined to a poison-bag in the roof ofthe mouth. When the viper seizes any small animal, the poison runs down through the fangs into the body of theanimal and kills it.
极北蝰的上腭有两颗又长又尖的牙， 也就是“毒牙”， 毒牙是中空的， 连接着上腭里面的毒囊。极北蝰抓住小动物的时候， 毒液就会通过毒牙流到动物体内， 把动物杀死。
The viper has also a number of small solid teeth. These have their points turned backwards, and help to hold the prey while it is being swallowed.
极北蝰也有很多坚硬的小牙齿， 齿尖是朝后的， 极北蝰吞掉猎物的时候， 这些牙可以抓住猎物， 不让猎物跑掉。
The ringed grass-snake has a double row of black spots running down its back. It has also two yellow patches or stripes on its neck. It has no poison-fangs. The ringed snake, like the viper, feeds on small animals, such as frogs and mice.
有环纹的水游蛇， 背上有两排黑点子， 脖子上还有两片黑色的斑点， 也叫条纹。水游蛇没有毒牙， 它跟蝰蛇一样， 以青蛙、老鼠一类的动物为食。
