What does "有蛋黄的迎春花" mean? 走进公园，我们感到春天真的来了。柳条迎着暖风轻轻地摆动，绿茵茵的草坪相扑了柔软的地毯。花都开了，有蛋黄的迎春花，粉红的桃花，白色的玉兰花，还有紫色的丁香花。

I'm reading this story above about these students going into a park. The part in bold I don't understand- as far as I know, it means "there were egg yolk winter jasmine flowers", but I'm sure that's not right.
迎春（学名：Jasminum nudiflorum），又称金腰带，香港俗称串串金，是木犀科素馨属的植物。早春先于叶子开放出黄色鲜艳的小花(bright yellow flowers)，给人们带来春意，所以花名曰迎春。

Winter jasmine (Jasminum nudiflorum) is a slender, deciduous shrub native to China. It is widely cultivated as an ornamental and is reportedly naturalized in France and in scattered locations in the United States.



Let's inspect the structure of the phrases.

蛋黄的迎春花
粉红的桃花
白色的玉兰花
紫色的丁香花  

These are appositives.
They have the same pattern, color + flower name.

The author uses two words (+ 的) to describe a color.
Thus, 蛋黄色 is simplified to 蛋黄, and 粉红色 to 粉红.

蛋黄(色)的花 egg yellow flowers