I thought that downloading the Xamarin NuGet would pull all the dependencies along with it?

I installed the Xamarin NuGet into my solution and tried to run the app when I received this error:
Exception while loading assemblies: System.IO.FileNotFoundException: Could not load assembly 'PCLCrypto, Version=2.0.0.0, Culture=neutral, PublicKeyToken=d4421c8a4786956c'. Perhaps it doesn't exist in the Mono for Android profile?
File name: 'PCLCrypto.dll'
at Java.Interop.Tools.Cecil.DirectoryAssemblyResolver.Resolve(AssemblyNameReference reference, ReaderParameters parameters) in /Users/builder/data/lanes/5749/75f8c683/source/xamarin-android/external/Java.Interop/src/Java.Interop.Tools.Cecil/Java.Interop.Tools.Cecil/DirectoryAssemblyResolver.cs:line 229
at Xamarin.Android.Tasks.ResolveAssemblies.AddAssemblyReferences(DirectoryAssemblyResolver resolver, ICollection`1 assemblies, AssemblyDefinition assembly, Boolean topLevel)
at Xamarin.Android.Tasks.ResolveAssemblies.Execute(DirectoryAssemblyResolver resolver) GridlockCardGame.Android

So I guess I'm missing an assembly somewhere, but I thought that the NuGet Manager would pull all that with the install.

Thank you for your time.