堆沙蠕虫分泌出一种胶状物将沙石粘合在一起形成壳装，这一点类似于淡水石蛾的幼虫。

Instead, it secretes a glue and USES this to stick bits of sand together to form its casing, in the way that a freshwater caddis fly larva does.

youdao

这些牡蛎壳被放置在大容器里，上面附着着数以亿计的牡蛎幼虫。

The shells are placed in tanks with hundreds of millions of oyster larvae.

youdao

在薄壳的保护下，幼虫还在发育。

While the larvae are still growing, they are protected by a thin shell.

youdao