无颚类脊椎动物

Any of various primitive aquatic vertebrates of the class Cyclostomata,lacking jaws and including the lampreys and hagfishes.

鳗类，鳗无颚的各种原始水生圆口纲脊椎动物中的一种，包括七鳃鳗和盲鳗

Included here are fishes having either a bony skeleton, such as a perch, or a cartilaginous skeleton, such as a shark, or those lacking a jaw, such as a lamprey or hagfish.

以具有鳍及用腮呼吸为特征的一种冷血水上脊椎动物，包括多骨骼鱼类，如河鲈；或软骨鱼类，如鲨鱼；或无颚鱼类，如七鳃鳗或八目鳗类鱼

Primitive jawless aquatic vertebrate: lampreys; hagfishes.

原始的无颚脊椎动物；七鳃鳗；八目鳗类鱼。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。