This scatter plot visualizes the Iris dataset, comparing sepal length against petal length for different iris species. The chart encodes each data point as a distinct shape, using the `d3.symbol` API with a `symbolsFill` scale to differentiate species, and includes a shape legend generated via `shapeLegend`. The visualization uses `d3.scaleLinear` for axes and `d3.scaleOrdinal` for species mapping, with custom axis and legend utilities built on D3's selection join pattern. Data is fetched as CSV from a GitHub repository and parsed with `d3.csvParse`.