Unable to find only Button Component for test

I have the following component and trying to perform tests on it.

I am able to find all other Components such as Element and Table.

But there is no result for finding Button object even though there are 2 of those.

Why is that the case?

To note Button, Element and Table component here are all custom components of mine.

Component being tested

export const MyComponent = () => (
  <div>
    <div style={{ margin: 20 }}>
      <Button onClick={() => {}}>
        Click Me!
      </Button>
      <Button onClick={() => {}}>
        Click Me!
      </Button>
    </div>

    <Element name="name">
      title
    </Element>
    <div>
      <Table name="name" />
    </div>
  </div>
);

export default MyComponent;

My test

describe('test page', () => {

     it('should click', () => {

    const mockSelectorToggle = jest.fn();
    const defaultProps = {};
    const initialise = props => shallow(<MyComponent {...defaultProps} {...props} />);
    const wrapper = initialise();

    // all the following found
    wrapper.find('div')
    wrapper.find('div').find('div')
    wrapper.find('Element')
    wrapper.find('Table')

    // nothing found. Why only Button not findable?
    // wrapper.find('Button')
    // wrapper.find('div').find('div').find('Button')

    // looking to test it this way
    wrapper.find('Button').first().simulate('click');
    expect(mockSelectorToggle).toHaveBeenCalled();
  });
});